@ballbearian covered this in his build thread starting here. Member 66Sprint (who recently passed) came up with a nice solution to the over advance issue.
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1961 CB72 The Long and Winding Road
- Thread starter Pridanc
- Start date
crazypj
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The centrifugal filter is actually much more efficient than paper one, particularly if you use more than 6K rpm.
There is a discussion about it on here somewhere
There is a discussion about it on here somewhere
Pridanc
Veteran Member
Hey crazypj,
Thanks for jumping in.
After all the time spent cleaning this little beast, and then reading up on centrifugal filters, I played a game of Roshambo to settle it as I was stuck.
Anyway there's no question a centrifuge is a super interesting way to keep the life blood clean but all said and done, I'm good with my choice here.
Stay well!
Thanks for jumping in.
After all the time spent cleaning this little beast, and then reading up on centrifugal filters, I played a game of Roshambo to settle it as I was stuck.
Anyway there's no question a centrifuge is a super interesting way to keep the life blood clean but all said and done, I'm good with my choice here.
Stay well!
crazypj
Veteran Member
- Joined
- Jun 5, 2020
- Total Posts
- 1,555
- Total likes
- 1,003
I had to look up Roshambo, never heard it before. 
ballbearian
Veteran Member
This is a great thread, really enjoying it. The work on cleaning the crank oilways and sludge traps in it were extra special.
The roll pin advance limiters must be holding up ok in mine so far.
The roll pin advance limiters must be holding up ok in mine so far.
Pridanc
Veteran Member
crazy, I only knew it because of my kids. When I grew up it was Rock-Paper-Scissors. You should have seen me trying to spell it. Thank gosh for the net, otherwise it would have been ugly.I had to look up Roshambo, never heard it before.
Pridanc
Veteran Member
#28
By now y'all know that as I leave the head and return to the bottom end, I can't imagine I'm not forgetting something so it'll be no surprise if I go back. If I do, I'll do my best to say I did in case anyone wants to see what googball thing I dropped.
Bottom end and gears.
Before jumping in, my brain has this tease of some little chicklet thing (in the red circle) that can be installed backwards as it can physically go back incorrectly, but am told the mechanism will not work properly or perhaps not as well as it would.. So I'm openly saying I think it is the little chicklet thing mentioned to me and is a part of the kick start mechanism. IF my brain serves me, you can put it in flipped (side to side, not end to end) and it will work but not well? Say I the expert here. As I do not remember if this is the "don't forget" bit that was mentioned to me, just make sure yours goes back together like this and you are covered.
No matter what, keep copious pictures as you take it apart and then put it all back the way you came. As mentioned, non of this is hard so just go slow and if something seems amiss, stop and think about it. Every piece is there for a reason and knowing its job also then means there is only one place it can go.
By now you know that once I've spent the time to get somewhere, like inside an old engine, I'm replacing all the parts that seem slightly too worn. Typically this is bearings, bushings and any seals. If you find parts not too worn in your opinion, you do not have to replace them but I'd replace the seals regardless. Regardless , this is your baby so the decision is yours. As I'm lazy. I tend to do the "out with the old" trick very often. So lets not mention this out-with-the-old to my wife as I rather enjoy being inside my old house. Deal?
Bearings, IMO, are good if not overly sloppy and roll without any glitch's, bumps, or complaints. Again mine felt ok and many passed my smell test, and I have a sensitive nose. One small example is this bush which was visibly worn in this circled area and although it was working at doing its job, it had to go IMO.
Once the lower half of the engine case was pulled of, it was time to clean and inspect. Old engines get nasty with age. OK, so do Old ppl like me.
We've discussed the bearings and bushes, but time to look hard at all those part that make up the transmission. Are the dogs on the gears good? Are the grooves in the shifting drum good? Is any part of the shift forks warn enough to impart slop? Some of this can impede function but equally bad, create imprecision when none was meant to be. In my case, this is a restoration and not just an exploration to catch what was getting long on tooth and then leaving it. A "resto" means making it new again. As I've spent more hours than I want to know exploring a resto, in many ways, is easier. Things that wear tend to have little chance of staying which means less time looking and agonizing. See? EZ-er...for me!
The Shift drum is at the very top. Looks like a rolling pin for small pizzas. Those curvy slots have some pins that ride in them, forcibly moving things around. When you operate the shift lever with your foot, you turn this drum which then moves the forks that select a gear. So look at the slots and the pin end of the bolts. All this is pointed out in purple.
In my experience forks tend to wear at the yellow circles. These can wear in more than just this area but this is typically the first area. Do they have to be perfect, well no, but those forks slide into a groove of two gears (one fork, one gear) as can be seen here above. Follow the blue lines. The half moon shape in the forks fit into the groove you see in the gear here. Just look for wear and if you think it too much, then phone-a-fren who's done this before, OR, look at a few pictures online. FleaBay typically has good pictures to help you decide.
Gears teeth should still have good form. Typically wear appears on one side of each tooth so if you see a side that no longer has the shape of the other side of the same tooth, time to think harder. And look at the dogs. That is the dogs the arrows point to below. (you can also see dogs on the gear above as another point of reference.)
Dogs are wear items but when these edges get too worn, you may want to replace the gear/gears. As you can see here these edges look sharp and precise. As they wear, these edges grow, as in the radius gets larger and less defined. If you look close, you can see that the sides of the dogs, lets call it their left and right side (not top or bottom?) are tapered in. They have a reverse cut which helps the dogs pull each other together under load. As the edges become rounded corners, there is less and less taper to grab to the dogs become less effective. Oh yes, the still work but shifting may need to be more authoritative with damage and age.
Before I leave this post, I want to mention my gear choices and why. This topic of to X or not to X is well documented. Nonetheless as a bum who's changed too many gears in quick change dog boxes for cars, I have gear charting stuff to take the gear ratio info and stare. These days this is not so innocent as it once was because I now drool. Not from a cool factor but just because. Hey, old dogs drool OK? Sad, I know.
I'm sure this is out there 100 times but what the heck, here it is again. And I've got numbers as well but a graph like this is generally all telling for me. If I need more info to help sway me, then I grab the numbers.
Forgive the blurriness as my computer and I were arguing and it won. However it sure seems to me to be clear enough to get the point across. Two charts are combined here.
One is the OE as delivered gear stack in this engine in all black. The chart with the purple bits is the famed X box. 1st gear and 4th gears are the same so share the same bit of black, but this displays
the new 2nd and 3rd gears and the change they bring in purple. Clearly, the X box has less rpm drop between the lower gears and in hind sight,
this may well be the right choice for many of y'all. But for me, a guy who doesn't care for stop-n-go traffic of a city, the OE box fits my bill for the
gentle rolling hills and curves I prefer. Top 3 gears are closer making it easier to keep the little buzzer on the boil. Like most everything here in the description of my journey, the choice is yours.
And even if you decide later you'd like to give the other stack a try, well step right up as you can! No need to buy any other parts. I will however toss out that this just might fall in the PITA range of things
to do on a Saturday afternoon.
Enjoy your weekend as I'm off to watch more of the LeMans 24. Talk later.
By now y'all know that as I leave the head and return to the bottom end, I can't imagine I'm not forgetting something so it'll be no surprise if I go back. If I do, I'll do my best to say I did in case anyone wants to see what googball thing I dropped.
Bottom end and gears.
Before jumping in, my brain has this tease of some little chicklet thing (in the red circle) that can be installed backwards as it can physically go back incorrectly, but am told the mechanism will not work properly or perhaps not as well as it would.. So I'm openly saying I think it is the little chicklet thing mentioned to me and is a part of the kick start mechanism. IF my brain serves me, you can put it in flipped (side to side, not end to end) and it will work but not well? Say I the expert here. As I do not remember if this is the "don't forget" bit that was mentioned to me, just make sure yours goes back together like this and you are covered.
No matter what, keep copious pictures as you take it apart and then put it all back the way you came. As mentioned, non of this is hard so just go slow and if something seems amiss, stop and think about it. Every piece is there for a reason and knowing its job also then means there is only one place it can go.
By now you know that once I've spent the time to get somewhere, like inside an old engine, I'm replacing all the parts that seem slightly too worn. Typically this is bearings, bushings and any seals. If you find parts not too worn in your opinion, you do not have to replace them but I'd replace the seals regardless. Regardless , this is your baby so the decision is yours. As I'm lazy. I tend to do the "out with the old" trick very often. So lets not mention this out-with-the-old to my wife as I rather enjoy being inside my old house. Deal?
Bearings, IMO, are good if not overly sloppy and roll without any glitch's, bumps, or complaints. Again mine felt ok and many passed my smell test, and I have a sensitive nose. One small example is this bush which was visibly worn in this circled area and although it was working at doing its job, it had to go IMO.
Once the lower half of the engine case was pulled of, it was time to clean and inspect. Old engines get nasty with age. OK, so do Old ppl like me.
We've discussed the bearings and bushes, but time to look hard at all those part that make up the transmission. Are the dogs on the gears good? Are the grooves in the shifting drum good? Is any part of the shift forks warn enough to impart slop? Some of this can impede function but equally bad, create imprecision when none was meant to be. In my case, this is a restoration and not just an exploration to catch what was getting long on tooth and then leaving it. A "resto" means making it new again. As I've spent more hours than I want to know exploring a resto, in many ways, is easier. Things that wear tend to have little chance of staying which means less time looking and agonizing. See? EZ-er...for me!
The Shift drum is at the very top. Looks like a rolling pin for small pizzas. Those curvy slots have some pins that ride in them, forcibly moving things around. When you operate the shift lever with your foot, you turn this drum which then moves the forks that select a gear. So look at the slots and the pin end of the bolts. All this is pointed out in purple.
In my experience forks tend to wear at the yellow circles. These can wear in more than just this area but this is typically the first area. Do they have to be perfect, well no, but those forks slide into a groove of two gears (one fork, one gear) as can be seen here above. Follow the blue lines. The half moon shape in the forks fit into the groove you see in the gear here. Just look for wear and if you think it too much, then phone-a-fren who's done this before, OR, look at a few pictures online. FleaBay typically has good pictures to help you decide.
Gears teeth should still have good form. Typically wear appears on one side of each tooth so if you see a side that no longer has the shape of the other side of the same tooth, time to think harder. And look at the dogs. That is the dogs the arrows point to below. (you can also see dogs on the gear above as another point of reference.)
Dogs are wear items but when these edges get too worn, you may want to replace the gear/gears. As you can see here these edges look sharp and precise. As they wear, these edges grow, as in the radius gets larger and less defined. If you look close, you can see that the sides of the dogs, lets call it their left and right side (not top or bottom?) are tapered in. They have a reverse cut which helps the dogs pull each other together under load. As the edges become rounded corners, there is less and less taper to grab to the dogs become less effective. Oh yes, the still work but shifting may need to be more authoritative with damage and age.Before I leave this post, I want to mention my gear choices and why. This topic of to X or not to X is well documented. Nonetheless as a bum who's changed too many gears in quick change dog boxes for cars, I have gear charting stuff to take the gear ratio info and stare. These days this is not so innocent as it once was because I now drool. Not from a cool factor but just because. Hey, old dogs drool OK? Sad, I know.
I'm sure this is out there 100 times but what the heck, here it is again. And I've got numbers as well but a graph like this is generally all telling for me. If I need more info to help sway me, then I grab the numbers.
Forgive the blurriness as my computer and I were arguing and it won. However it sure seems to me to be clear enough to get the point across. Two charts are combined here.
One is the OE as delivered gear stack in this engine in all black. The chart with the purple bits is the famed X box. 1st gear and 4th gears are the same so share the same bit of black, but this displays
the new 2nd and 3rd gears and the change they bring in purple. Clearly, the X box has less rpm drop between the lower gears and in hind sight,
this may well be the right choice for many of y'all. But for me, a guy who doesn't care for stop-n-go traffic of a city, the OE box fits my bill for the
gentle rolling hills and curves I prefer. Top 3 gears are closer making it easier to keep the little buzzer on the boil. Like most everything here in the description of my journey, the choice is yours.
And even if you decide later you'd like to give the other stack a try, well step right up as you can! No need to buy any other parts. I will however toss out that this just might fall in the PITA range of things
to do on a Saturday afternoon.
Enjoy your weekend as I'm off to watch more of the LeMans 24. Talk later.
Last edited:
crazypj
Veteran Member
- Joined
- Jun 5, 2020
- Total Posts
- 1,555
- Total likes
- 1,003
Suzuki used very similar sprag mechanism for decades on gear change drum. If you asked me which way it went I wouldn't remember without looking at it.
Suzuki had a left and right with offset slot for spring.
Those transmission gears look brand new?
Didn't Honda make a close ratio set for the road race conversion? (and maybe a wide ratio/extra low first gear for desert racers?)
CB72/77 is one of the few motors I've never had in pieces but as the first 'real' bike I ever fell off has a special memory for me. (about 55 years ago)
Suzuki had a left and right with offset slot for spring.
Those transmission gears look brand new?
Didn't Honda make a close ratio set for the road race conversion? (and maybe a wide ratio/extra low first gear for desert racers?)
CB72/77 is one of the few motors I've never had in pieces but as the first 'real' bike I ever fell off has a special memory for me. (about 55 years ago)
Pridanc
Veteran Member
You are now punching way over my head. By that I mean there could well be a race sets of ratios and there might even be a 5 speed but those are just whispers to me as I knew that none of that was on my radar even if cool so I did no digging.
And yes, those two gear are pictures off of Fleabay. You don't think I had the foresight to take pictures of mine did you? Sad when I set out to take more pictures than you possibly could. Clearly I was off my meds that day. But good eye, as yes. those are spanking new as examples but if you look closely to the one picture of it assembled prior to coming all apart, the dogs look good and were.
Stay well.
Last edited:
Pridanc
Veteran Member
#29
Lets finish up the engine. I realize that for many, rebuilding an engine can be daunting but IMO it needn't be.
If you follow these suggestions , it will be hard to screw up but above all don't doubt yourself! Nothing here is rocket science so take it a step at a time. Read up on the task ahead so when you are doing it, most of it won't be completely foreign to you.
1) Get hold of the shop manual.
I got this manual inside a bunch of info I purchased from Bill Silver. Manuals aside, there is so much interesting info separate from manual I got from BIll I still go back and read them to see what I missed. Simply marvelous information.
2) Make sure you have a parts book. (got it with the Shop manual etc) I've seen some that have too few pages so watch out for those. Bill's is complete for this bike. There are some type-O's in the book but your eyes will not lead you astray. I'd bet all this info can be found here on the forum.
3) Take copious pictures as you disassemble so that if in doubt, you can go to your detailed and plentiful pictures. Do not use me as an example as clearly I didn't follow my own mantra.
4) If / when taking things apart that are known to have small bits that can fall at the most inopportune times, give yourself a safety net. If I have a large area to cover, I use old towels laid down because nothing bounces after hitting a towel so bits wont' get lost. Most common for me is a very large cookie pan with said towel. No matter what you choose, just think about what you'll do IF (when) something sneaks out on its own. BTW , once you know how this engine, or anything your are working on goes together, you will forego the towels. It a process.
5) You can always "phone a friend" aka text or email "those in the know". This very forum as one of those friends so use it. People really like to help so take advantage of that.
As you may now know, the CB72 / 77 crankshafts are made up of 5 pieces and their assembly takes a press and great patience. Think about it. all the pieces need to go together such that all sections are the correct length (and by then, naturally, the OA length of the crank would be in spec), that all parts are "square" to each other, IE, the crank and parts are flat, or perpendicular to each other where it matters and finally, that each part is rotationally in the exact spot. Oh, and DO NOT forget the rods, their needle bearings and cages. I promise that if you did? You'd be so ready to cry.
BTW, it takes lots of pressure to get these parts to become one again. If memory serves 7-10 tons. The moaning of the press is indicative that it is having to work. A lot. My brain hurts to even contemplate doing this. Thankfully my man Tim Miller was well versed. Even if I had the capability to do this, that is a press that was in the 15-20 ton range, not sure I would have attempted it myself. A lot of that is my patience level and nor do I need to learn on the only crankshaft I have. Yes, I am happy to admit that I am a slacker
Old news. Pictures, what pictures? How I don't have a pic of the crank with rods just laying on the bench is beyond me. Sorry.
Now we are going to reverse the steps taken do dismantle the engine. As I haven't done a CB72 before, I'm not sure is there is a huge reason for a specific installation order of these large parts. Just take your time.
Anyway, drop the built-up crankshaft back in making absolutely certain that the bearings fit over their pins in the crankcase. I'm not sure it really matters since this engine had a pin pushed into the case without engaging the bearing as intended ,yet there was no noticeable damage at disassembly. The pins are there for a reason however so there's that. Indeed, this bearing survived and you can see here where this pin got pushed back up followed with some oil-resistant epoxy placed on the pin's back-side hole hoping to keep it in place. Yes, the crank was laid back into the case carefully making sure the pins were in place and that the bearings were all happy.
The picture below sucks (by now, no such a surprise right?) but is an attempt to better show what I'm talking about here. The Red arrow points to the pin that was pushed into the case and was not engaged in the bearing. Angle of the picture doesn't show that the pin is flush with the surface. The green arrow shows a pin still sitting proud as they all are meant to be. And then the epoxy repair to the hole after the pin was pushed back up into place.
Next the gear stacks and as you are doing this, watch that the three seals are nice and happy. One on the crankshaft, one on each of the gearbox shafts. There are only seals on one side of each shaft. The other side of the shafts, the clutch side, all live in oil so no oil seal needed. If the seals end up cocked, this will be as my Dutch friend says: " Not so very good". Truth is, I'm not sure I've ever had a seal **** itself when being trapped by two crankcase halves. Just look at them and if they look close to vertical, you are good. The halves clamping together will have them behave.
After a final clean of the mating surfaces of the two crankcase halves, apply your choice of sealant to the surface staring up at you. (not both surfaces) Like cards its "thin to win" as you want to avoid extra slop. As an old air cooled Porsche guy, I used something called Drei-Bond and or Loctite 574 but don't recall what was used here. But don't panic as there are several great options other than my go to sealants mentioned above as all are excellent: Hondabond (or its equivalents: ThreeBond 1184/1194, Yamabond, or Permatex Moto-Seal.) The only product here I've not used is Permatex Moto-Seal but lets face it, Permatex has an outstanding reputation so again, my thoughts are that each of these will easily get the job done.
Now Drop the Bottom half of the crankcase onto this bunch of bits and voila...we are getting there.
Below is Honda's suggested torqueing sequence for the fasteners of this lower crankcase. Do a search here on the forum as there are some great suggestions that have a suggestions of a different tightening sequence. Of course, you can't go wrong doing it the way Honda did back in the day so if you follow this guide, you are covered regardless. Torques for these is a bit vague so do some spelunking. Again, this forum then "around", as the crankcase torque specs are one of those areas where many points back to general Honda practices (at times I'm not sure what that is) because the original factory manuals are IMO surprisingly vague on the smaller bolts. As I'm a big old chicken, I tend to go slightly under or choose a median value. This I tend to default to a diameter-based approach so M8s are around 15 ft-lbs, M6s 7–10 ft-lbs, always staged in three steps. 1) snug, 2) 50% and 3) use the listed torques mentioned here or what you feel best per forums or others with real knowledge of these. I do not have any hard knowledge but would not hesitate to use the numbers I list. Let your conscience be your guide.
Now you can start adding all the bits that came off prior to splitting the case. And while you are here, don't forget to verify placement and function of the shifting mechanisms. If after full assembly you feel you got it wrong you can always go back and look at it but you'll have to drop the outside the clutch cover which holds oil so be ready for a tsunami of oil. Moral here is to work the shift mechanism before moving on as in change gears etc. Whilst manually changing gears, now might be a great time to install your neutral gear indicator sensor to test on the bench which you may recall lives very near the chain drive sprocket on the right side of the engine? This is a simple on-off switch which activates a lamp in the Nacelle when in neutral.
Here is a picture of the neutral switch installed and regret that the only pic I have is this "pre clean" picture. Nasty.
Gear Selector mechanism. Resplendent in dirt. Dang it all as I've clearly misplaced some photos as I'm not seeing my clean bits. Seriously though, work this and watch how it does its job. Very cool if you ask me. When you are working it, you may have to "jog" the chain sprocket since the engine isn't running so gears are just sitting there.
I'll drop a few more pictures of the before the bottom of the crankcase was dropped back on. I'm so irritated with my lack of pictures at the moment but spilt milk and all... you know the rest.
Reminder here. GREEN words indicate I came back and added something. It is lame here, but I've no doubt I'll be going back and adding sections I forgot, then it will be a sea of green.
Later
Lets finish up the engine. I realize that for many, rebuilding an engine can be daunting but IMO it needn't be.
If you follow these suggestions , it will be hard to screw up but above all don't doubt yourself! Nothing here is rocket science so take it a step at a time. Read up on the task ahead so when you are doing it, most of it won't be completely foreign to you.
1) Get hold of the shop manual.
I got this manual inside a bunch of info I purchased from Bill Silver. Manuals aside, there is so much interesting info separate from manual I got from BIll I still go back and read them to see what I missed. Simply marvelous information.
2) Make sure you have a parts book. (got it with the Shop manual etc) I've seen some that have too few pages so watch out for those. Bill's is complete for this bike. There are some type-O's in the book but your eyes will not lead you astray. I'd bet all this info can be found here on the forum.
3) Take copious pictures as you disassemble so that if in doubt, you can go to your detailed and plentiful pictures. Do not use me as an example as clearly I didn't follow my own mantra.
4) If / when taking things apart that are known to have small bits that can fall at the most inopportune times, give yourself a safety net. If I have a large area to cover, I use old towels laid down because nothing bounces after hitting a towel so bits wont' get lost. Most common for me is a very large cookie pan with said towel. No matter what you choose, just think about what you'll do IF (when) something sneaks out on its own. BTW , once you know how this engine, or anything your are working on goes together, you will forego the towels. It a process.
5) You can always "phone a friend" aka text or email "those in the know". This very forum as one of those friends so use it. People really like to help so take advantage of that.
As you may now know, the CB72 / 77 crankshafts are made up of 5 pieces and their assembly takes a press and great patience. Think about it. all the pieces need to go together such that all sections are the correct length (and by then, naturally, the OA length of the crank would be in spec), that all parts are "square" to each other, IE, the crank and parts are flat, or perpendicular to each other where it matters and finally, that each part is rotationally in the exact spot. Oh, and DO NOT forget the rods, their needle bearings and cages. I promise that if you did? You'd be so ready to cry.
BTW, it takes lots of pressure to get these parts to become one again. If memory serves 7-10 tons. The moaning of the press is indicative that it is having to work. A lot. My brain hurts to even contemplate doing this. Thankfully my man Tim Miller was well versed. Even if I had the capability to do this, that is a press that was in the 15-20 ton range, not sure I would have attempted it myself. A lot of that is my patience level and nor do I need to learn on the only crankshaft I have. Yes, I am happy to admit that I am a slacker
Old news. Pictures, what pictures? How I don't have a pic of the crank with rods just laying on the bench is beyond me. Sorry.
Now we are going to reverse the steps taken do dismantle the engine. As I haven't done a CB72 before, I'm not sure is there is a huge reason for a specific installation order of these large parts. Just take your time.
Anyway, drop the built-up crankshaft back in making absolutely certain that the bearings fit over their pins in the crankcase. I'm not sure it really matters since this engine had a pin pushed into the case without engaging the bearing as intended ,yet there was no noticeable damage at disassembly. The pins are there for a reason however so there's that. Indeed, this bearing survived and you can see here where this pin got pushed back up followed with some oil-resistant epoxy placed on the pin's back-side hole hoping to keep it in place. Yes, the crank was laid back into the case carefully making sure the pins were in place and that the bearings were all happy.
The picture below sucks (by now, no such a surprise right?) but is an attempt to better show what I'm talking about here. The Red arrow points to the pin that was pushed into the case and was not engaged in the bearing. Angle of the picture doesn't show that the pin is flush with the surface. The green arrow shows a pin still sitting proud as they all are meant to be. And then the epoxy repair to the hole after the pin was pushed back up into place.
Next the gear stacks and as you are doing this, watch that the three seals are nice and happy. One on the crankshaft, one on each of the gearbox shafts. There are only seals on one side of each shaft. The other side of the shafts, the clutch side, all live in oil so no oil seal needed. If the seals end up cocked, this will be as my Dutch friend says: " Not so very good". Truth is, I'm not sure I've ever had a seal **** itself when being trapped by two crankcase halves. Just look at them and if they look close to vertical, you are good. The halves clamping together will have them behave.
After a final clean of the mating surfaces of the two crankcase halves, apply your choice of sealant to the surface staring up at you. (not both surfaces) Like cards its "thin to win" as you want to avoid extra slop. As an old air cooled Porsche guy, I used something called Drei-Bond and or Loctite 574 but don't recall what was used here. But don't panic as there are several great options other than my go to sealants mentioned above as all are excellent: Hondabond (or its equivalents: ThreeBond 1184/1194, Yamabond, or Permatex Moto-Seal.) The only product here I've not used is Permatex Moto-Seal but lets face it, Permatex has an outstanding reputation so again, my thoughts are that each of these will easily get the job done.
Now Drop the Bottom half of the crankcase onto this bunch of bits and voila...we are getting there.
Below is Honda's suggested torqueing sequence for the fasteners of this lower crankcase. Do a search here on the forum as there are some great suggestions that have a suggestions of a different tightening sequence. Of course, you can't go wrong doing it the way Honda did back in the day so if you follow this guide, you are covered regardless. Torques for these is a bit vague so do some spelunking. Again, this forum then "around", as the crankcase torque specs are one of those areas where many points back to general Honda practices (at times I'm not sure what that is) because the original factory manuals are IMO surprisingly vague on the smaller bolts. As I'm a big old chicken, I tend to go slightly under or choose a median value. This I tend to default to a diameter-based approach so M8s are around 15 ft-lbs, M6s 7–10 ft-lbs, always staged in three steps. 1) snug, 2) 50% and 3) use the listed torques mentioned here or what you feel best per forums or others with real knowledge of these. I do not have any hard knowledge but would not hesitate to use the numbers I list. Let your conscience be your guide.
Now you can start adding all the bits that came off prior to splitting the case. And while you are here, don't forget to verify placement and function of the shifting mechanisms. If after full assembly you feel you got it wrong you can always go back and look at it but you'll have to drop the outside the clutch cover which holds oil so be ready for a tsunami of oil. Moral here is to work the shift mechanism before moving on as in change gears etc. Whilst manually changing gears, now might be a great time to install your neutral gear indicator sensor to test on the bench which you may recall lives very near the chain drive sprocket on the right side of the engine? This is a simple on-off switch which activates a lamp in the Nacelle when in neutral.
Here is a picture of the neutral switch installed and regret that the only pic I have is this "pre clean" picture. Nasty.
Gear Selector mechanism. Resplendent in dirt. Dang it all as I've clearly misplaced some photos as I'm not seeing my clean bits. Seriously though, work this and watch how it does its job. Very cool if you ask me. When you are working it, you may have to "jog" the chain sprocket since the engine isn't running so gears are just sitting there.
I'll drop a few more pictures of the before the bottom of the crankcase was dropped back on. I'm so irritated with my lack of pictures at the moment but spilt milk and all... you know the rest.
Reminder here. GREEN words indicate I came back and added something. It is lame here, but I've no doubt I'll be going back and adding sections I forgot, then it will be a sea of green.
Later
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That looks pretty clean to me. My C77 selector was in a much more abused state lol
Pridanc
Veteran Member
#30
More engine stuff.
Not that it matters to 99.99% of us, but thought I'd mention that through the years, and for various reasons only known by Honda (not a slam, just me talking) our Type I engines are considered the 180° engines vs. the Type 2 being considered a 360°. This has to do with the crankshaft layout. These choices affect several things in the engine from power delivery to balance and more. See link below for some education.
Those in the know, most definitely not me, have the knowledge and only have to glance at the bike and can say what type engine that bike uses. I have to look at the points cover Rt side of the engine. You know, the cheat sheet.
The engine in this bike is a Type 1 180 degree engine with the "whack a mole" pistons. I don't have an open picture of the Type 2 but you can see the difference here.
I was going to pontificate about "why this firing order over another" but know that a far better explaination sits with much smarter people than I so follow this link to a gent well worth a listen too. In this case he discusses the various differences in vertical twin firing orders which encompasses the Honda Type I and Type 2 by default. His presentations are such that even this cave man gets it. And besides this video, he has many engine related videos you will enjoy, I promise.
Straightened some fins, cleaned 'er on up. OK, lets admit it is cleaner but the backgrounds affect the shine here too.
Couple of more next entry.
More engine stuff.
Not that it matters to 99.99% of us, but thought I'd mention that through the years, and for various reasons only known by Honda (not a slam, just me talking) our Type I engines are considered the 180° engines vs. the Type 2 being considered a 360°. This has to do with the crankshaft layout. These choices affect several things in the engine from power delivery to balance and more. See link below for some education.
Those in the know, most definitely not me, have the knowledge and only have to glance at the bike and can say what type engine that bike uses. I have to look at the points cover Rt side of the engine. You know, the cheat sheet.
The engine in this bike is a Type 1 180 degree engine with the "whack a mole" pistons. I don't have an open picture of the Type 2 but you can see the difference here.
I was going to pontificate about "why this firing order over another" but know that a far better explaination sits with much smarter people than I so follow this link to a gent well worth a listen too. In this case he discusses the various differences in vertical twin firing orders which encompasses the Honda Type I and Type 2 by default. His presentations are such that even this cave man gets it. And besides this video, he has many engine related videos you will enjoy, I promise.
Straightened some fins, cleaned 'er on up. OK, lets admit it is cleaner but the backgrounds affect the shine here too.
Couple of more next entry.
Pridanc
Veteran Member
#31
Couldn't stop and leave you hanging.
Baby steppin'.
Later...!
Couldn't stop and leave you hanging.
Baby steppin'.
Later...!