1972 CB450 K5 Hot Mess

Looks good, other than the circlip for the shift shaft which looks a bit too expanded - is it fully in the groove in the shift shaft? Did you put the circlip on so the totally flat side is facing outward as well?
 
Looks good, other than the circlip for the shift shaft which looks a bit too expanded - is it fully in the groove in the shift shaft? Did you put the circlip on so the totally flat side is facing outward as well?
New circlip from DSS and the clip is all the way in the groove and I double/triple checked to make sure the flat side is facing out. With my eyes even with a magnify glass it was bit hard to tell and then every time I handled it before I put it on I was afraid I had flipped it so had to recheck again. :cool: I am able to just shift the spindle back and forth a few thousandths and it appears to be locked in well.
 
New circlip from DSS and the clip is all the way in the groove and I double/triple checked to make sure the flat side is facing out. With my eyes even with a magnify glass it was bit hard to tell and then every time I handled it before I put it on I was afraid I had flipped it so had to recheck again. :cool: I am able to just shift the spindle back and forth a few thousandths and it appears to be locked in well.
The end play sounds right, but the clip looks stretched open a bit, that's all. If you can push it by one tang and it rotates in the groove then it's seated, I'm just always concerned that they fit snugly on the shaft.
 
By neutral safety you mean the indicator, right?

Or did you rig in the late 70’s-80’s interlock that prevents starting without being in neutral?
 
By neutral safety you mean the indicator, right?

Or did you rig in the late 70’s-80’s interlock that prevents starting without being in neutral?
Good catch on the verbiage, I should have said neutral light switch. :)
 
Good. I was hoping you hadn’t got a wild hair for some reason and over complicated the ignition circuit. I got sick of it on mine and just bypassed it.
 
Good. I was hoping you hadn’t got a wild hair for some reason and over complicated the ignition circuit. I got sick of it on mine and just bypassed it.
No I can not see myself making my life more complicated and I am not a big fan of how industry has to add yet another safety device on something simple because an idiot managed to injure or kill themselves. My favorite example is the new gas cans which require at least 2 people to add fuel to a lawn mower or a new car, one to lift and lift and hold the can and one to operate/over ride the safety mechanisms.
 
My favorite example is the new gas cans which require at least 2 people to add fuel to a lawn mower or a new car, one to lift and lift and hold the can and one to operate/over ride the safety mechanisms.
Yes, the world has been compensating for stupid people for far too long. I hear you about modern fuel cans, I just added a 5 gallon can to my group and even though it has one of the better spout designs, the handles are not properly designed for ease of use while fiddling with the ridiculous valve opening method.
 
Always return the torque setting of the torque wrench to the lowest torque after usage ;)
Thanks I did do that after I took the photo but a reminder is always good. WE got well trained in the Air Force on taking care of our precision tools especially if we dropped one and it had to go back to have the calibration checked.
 
Question for those with more experience on these engines on piston ring end gap. I separated the sets by by left and right for their respective cylinders.



Ring Gap.jpg

I checked the gap on the new rings and got the following, measured in thousandths of an inch.


Left Right

Oil 13 13

2nd 12 15

Top 12 12


My question is should I be OK with the gap at the minimum clearance on both top rings and the one 2nd ring or would I be better off taking off a bit to avoid the possible chance of piston seizure? Had a bad experience on a 650 BSA top end rebuild years ago and had to redo it. Thanks for the advice.
 
Yeah, I might take the 3 that are right at .012" and open them up to .014" or .015" to be safe, considering the upper limit is .031" you'll be fine.
 
I looked at the photo of the open side to see what @ancientdad was talking about with the clip, and I was impressed with how many scars there are from a broken chain. I had a bike that felt like the clutch was sticking some and it turned out to be the clutch release rod was slightly bent from getting whacked by a broken chain. While yours is open I'd take out the push rod and just roll it across some known flat surface to check it.
 
I looked at the photo of the open side to see what @ancientdad was talking about with the clip, and I was impressed with how many scars there are from a broken chain. I had a bike that felt like the clutch was sticking some and it turned out to be the clutch release rod was slightly bent from getting whacked by a broken chain. While yours is open I'd take out the push rod and just roll it across some known flat surface to check it.
I went back and looked again, and it even chipped the edge of the lower front screw hole in the lower case. I once saw a clutch rod that was hit hard enough that it also cracked the steel mainshaft small end bearing where the hole is for the clutch rod, knocked a chunk out of it.
 
I went back and looked again, and it even chipped the edge of the lower front screw hole in the lower case. I once saw a clutch rod that was hit hard enough that it also cracked the steel mainshaft small end bearing where the hole is for the clutch rod, knocked a chunk out of it.
I am not sure if that was the chain or the PO as the threads are stripped about a1/4 inch in the broken area of the hole but there is quite a bit of good thread further down so may have to use a little longer screw then what it calls for but should be OK. I will double check the clutch rod as well.
 
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Rob, not to be critical but I agree with AD that your circlip does seem a bit open. For comparison, here is a shot of mine with a Honda OEM circlip. Maybe the groove on your shaft has some damage from the thrown chain.
circlip.jpg
 
Appreciate the extra look and I will check it tomorrow and see if it is snapped in properly or not. I can also try the clip on another shift spindle that I have to see if there is a difference in how it sits in the groove. I de finely don't want it to come loose which is why I ordered a new clip from DSS.
 
Standard hardware like circlips can be used only once, on top of that, when mounting, stretch them minimal. However, I rather use a different type of clip for this application, a more secure one, preferable the second clip in the image below (DIN 6799) instead of the circlip in the third image. It's a **tch to mount, but once in place, it will hold. I use the stainless spring steel version for mounting outside the engine. It was a gamble, because the clip has less area to hold it in place, but the clamping force is way higher. Until today, I didn't have any issues with that type of my bikes. If you choose for a standard circlip, use the fourth type in the picture, also stainless steel spring steel version. the clamping force is the same as the standard clip (image three).

If you buy these in a hardware store, the price is around 10-20 cents a piece, and if buying in bulk, even cheaper.

clips.jpg
 
I couldn't stand it so I went to the garage last night and checked the circlip on the spindle and confirmed it is locked well and good in the groove on the spindle and I can push it around by a tang with quite a bit of force. I also got out the 2nd spindle I have and compared the old circlip with an extra new one I had purchased from DSS and the tangs look a bit larger on the new one and the fit on the spindle is the same as the spindle installed in the engine. I also took my hard plastic mallet and gave the spindle a few light whacks on the end just to test the clip to see if would push loose and it held in place. I think @jensen's suggestion of an E-Clip is certainly worth considering especially in stainless. I have had to remove and install them without any type of special tool and they are a bear. With any knock or impact that would dislodge an e clip you probably bigger problems. :)
 
I couldn't stand it so I went to the garage last night and checked the circlip on the spindle and confirmed it is locked well and good in the groove on the spindle and I can push it around by a tang with quite a bit of force. I also got out the 2nd spindle I have and compared the old circlip with an extra new one I had purchased from DSS and the tangs look a bit larger on the new one and the fit on the spindle is the same as the spindle installed in the engine. I also took my hard plastic mallet and gave the spindle a few light whacks on the end just to test the clip to see if would push loose and it held in place. I think @jensen's suggestion of an E-Clip is certainly worth considering especially in stainless. I have had to remove and install them without any type of special tool and they are a bear. With any knock or impact that would dislodge an e clip you probably bigger problems. :)
My concern was that the tips of the circlip looked to be a bit wider apart than what you'd expect if it was fully seated, as if maybe the tips got spread apart a bit during installation. They're a bit difficult to handle while moving across a long shaft like that (particularly if your circlip pliers aren't perfectly suited) and it isn't hard to over-expand them. If it passes the test of staying fully in the groove, then you'll be fine.
 
I don't know if DSS delivers genuine circlips, but if DSS buys in bulk, maybe the size is wrong (ID). A correct ID circlip should not look like this.
 
A step forward and then 2 steps back. With the concern expressed on the fit of the shift spindle circlip I have decided to order another one from another vendor to see how it looks but holding off until I have a few other things I need to order.

I decided to start getting things ready to install the pistons, cylinder and head. Filed the 3 compression rings that were at minimum spec so that all 4 were at 15 thousandths which provides me some peace of mind. Next step put the rings on the pistons and it was a bit of fun with the original Honda rings and the the one piece oil rings. I had visions of hearing a nasty twang and seeing part of a ring go flying but got them on no problem other than sore thumbs. Next step was to get the pistons mounted on the connecting rods using new piston pins and clips from DSS. Unwrapped the pins and made sure they fit the pistons and rods no problem and confirmed the orientation I want to install the pistons. Long story short one of the clips was about 10 thousandths too long and would not fit in the groove due to overlap of the other end of the clip. I probably could have forced it in but I didn't to take the chance of ruining a piston for a clip. Also it is not the grove another clip snapped right in and then I had the same issue with that clip on the other piston. After some thought I used the piston ring filer to take a bit off the clip and then it snapped in no problem. Here is a picture of the snap ring in a piston before I filed it.

IMG_4616.JPG


Has anyone seen this issue before? In poor light and if someone was in a hurry it would have been easy to think it had snapped in properly. I am debating if I should replace that snap ring or no not so on hold with getting the cylinder installed.
 
I'm one to always double and triple check wristpin clips, too much at risk there not to. Can't say I've ever gotten any clips that were so long they overlapped though.
 
I'm one to always double and triple check wristpin clips, too much at risk there not to. Can't say I've ever gotten any clips that were so long they overlapped though.
It was a new one to me as well and I kept looking for another explanation like something in the groove keeping the clip from seating.
 
Maybe it's because of the clip overlap, but it almost looks like the clip has a larger diameter than the groove in the piston and is not seating all the way into the groove. Check the area highlighted by the yellow arrow.
IMG_4616.JPG
 
Good catch on that. I will have to take a look at it tomorrow and see if I see that gap there. I ordered a couple of new clips as well as a couple of shift spindle circlips from Partzilla so hopefully I can resolve my clip issues. Is clipitis a thing?
 
Good catch on that. I will have to take a look at it tomorrow and see if I see that gap there. I ordered a couple of new clips as well as a couple of shift spindle circlips from Partzilla so hopefully I can resolve my clip issues. Is clipitis a thing?

Definitely a thing. In order 4 every time I need one. One to bend. One to lose. One to use and a backup.
 
Are you able to rotate the clip at all?
I tried to shift the clip that was overlapping a bit but couldn't get it to move and really didn't try too hard because I didn't want the tool to slip and gouge the piston. About to call it a night but will take a look tomorrow.
 
Are these new pistons ? And did the clips come in a Honda bag ?

I order my clips at Honda direct, the only way to be sure of getting genuine clips. I know that CMS, but DSS probably also, sell aftermarket clips. That's not necessarily bad, but you don't know what you get. And yes, I order the by the dozen, since these clips are sensitive to over-bending. You need to do it in one move, in one time. If you tried to put them in more than a few times, practice with them until you can do it in one movement. Then take it out and place a new one.
 
The pistons are new, ART brand, which I understand is very reputable and made Honda pistons. The clips came in a zip lock bag marked with the correct part number so I am emailing DSS to confirm if the clips are genuine Honda or aftermarket. I will update after I get a reply.
 
I received a reply from Matt at DSS and confirmed that the piston pin clips are Honda. He apologized and asked if I wanted him to send replacements and I told him yes. I suppose no matter who makes something there is always a chance of a defect.
 
Honestly, it looks like that one just got bent slightly oval, which would explain both the not quite seated in the groove and the overlapping ends. It happens.
 
Honestly, it looks like that one just got bent slightly oval, which would explain both the not quite seated in the groove and the overlapping ends. It happens.
Certainly a possibility although I only used my fingers to install and tried to only use enough pressure jut to get the clip in place. Hopefully the new ones will do the trick I can get the cylinders and head installed.
 
Certainly a possibility although I only used my fingers to install and tried to only use enough pressure jut to get the clip in place. Hopefully the new ones will do the trick I can get the cylinders and head installed.
AQL (Acceptable Quality Level) for most hard good manufacturing has a Critical Defect rate of about 2.5%, not to mention shipping and storage and who knows how many hands those things passed through on their way to you. When it comes to little stuff like this and master links and fasteners I always try to order at least 2 extras for this reason. It has led to a rather large disorganized tray carefully labeled "Random/Weird Stuff" that sits in the parts cabinet until it fills up, then sorted and boxed, forgotten about and reordered again a couple years later.
 
AQL (Acceptable Quality Level) for most hard good manufacturing has a Critical Defect rate of about 2.5%, not to mention shipping and storage and who knows how many hands those things passed through on their way to you. When it comes to little stuff like this and master links and fasteners I always try to order at least 2 extras for this reason. It has led to a rather large disorganized tray carefully labeled "Random/Weird Stuff" that sits in the parts cabinet until it fills up, then sorted and boxed, forgotten about and reordered again a couple years later.
I know what you mean on buying extra stuff, I typically find the small part that I knew I had but can't find shortly after buying another one.
 
Replacement piston pin clips are supposed to arrive in the mail later today so hoping to get moving again. After installing the new clip next steps are install the cylinders and then the head. I have the timing mark on the rotor set and the cam timing marks lined up and of course will recheck as I go along. I have the 4into1 gasket set and overall the gaskets and seals look good to me including the head gasket. I did order a genuine Honda cylinder base gasket from DSS with one of my orders awhile back as I had seen several threads where people have had trouble with leaks there with aftermarket gaskets. My sealing surfaces are in good shape but I am wondering if there are any areas I should consider using a bit of gasket sealant on that are know know to be problematic.
 
but I am wondering if there are any areas I should consider using a bit of gasket sealant on that are know know to be problematic.
In my experience, the narrow area of the head gasket at the front and rear of the cam chain tunnel needs a thin smear of sealer. I've always used silicone sealer modestly, but Hondabond is fine there too. And it can't hurt to put a little on the head gasket around (but not too close to) the flat o-rings where the oil flow goes up the two right hand cylinder studs. I do this on both sides of the gasket in both areas, but again, not too close to the openings for the flat o-rings for obvious reasons. On my red 450, I also used Hondabond on the base gasket just as insurance, though I've never had any sealing issues there personally.
 
Received 4 replacement piston pin clips although only needed one and a new clip went in place no problem first try. Kudos to DSS customer service for taking care of this issue very quickly with no fuss. The wait was not wasted though because I realized that I had not cleaned up the cylinder head nut and washers. I dug out the zip lock bags with both sets of hardware from the 72 CB and the 71 CL donor engine and once again the build is a bit more CL than CB. The nuts from the CB were much more corroded and there were no copper sealing washers just two slightly larger steel washers the PO must have substituted for some reason. Luckily the nuts and steel washers from the CL were in much better shape and are are soaking in Evapo-Rust right now. There were also 2 copper sealing washers and they are in good shape as well and I have annealed them with my propane torch and cleaned up so good to go there.
 
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Slow and steady now, double check everything. You're doing stuff you don't want to have to do again. I kept stopping and walking away, thinking it through and looking for things I had to do that I might forget. There was a pad on my workbench where I could scribble down notes to remember one thing or another. Since the engine I am working on is still not running there's no way to know if I overlooked something anyway.
 
Slow and steady now, double check everything. You're doing stuff you don't want to have to do again. I kept stopping and walking away, thinking it through and looking for things I had to do that I might forget. There was a pad on my workbench where I could scribble down notes to remember one thing or another. Since the engine I am working on is still not running there's no way to know if I overlooked something anyway.
Honestly sometimes I feel like I am moving slower than a glacier until I remember something I almost forgot or did forget and have to redo a step.
 
After taking another look went ahead and installed the cylinder. I didn't use any adhesive on the base gasket as both sealing surfaces looked really good and it is a genuine Honda gasket. Staggered the rings about 1/3 away from each other and lubed everything up with motor oil. Cylinders went down over the rings with minimum effort just using my fingers and the tip of the plastic handle of an artist brush. Cylinder settled on the base gasket with just a bit of wiggling and looks good all the way around.

IMG_4623.JPG

IMG_4624.JPG
 
While getting ready to install the head I noticed that the hole in the head gasket that is supposed to go over the knock pin on the left side was too small. I ended up using a 1/2 inch drill to open the hole up in the gasket and then dress it with a file. It fit perfectly so hopefully no issues there. I do have a question about the flat seals that go over the knock pins on the right side. Should you just put the seals on the knock pins and then lay the gasket on top or should some of the seal be through the hole in the gasket? I am planning on using a bit Hondabond around them but want to know the correct installation procedure.


Before using a drill to open the hole in the gasket.

IMG_4627.JPG

Should some of the flat seal be showing on this side of the gasket?

IMG_4628.JPG
 
Yes, some of the flat o-ring should stick up inside that hole in the head gasket. I've had to open up some head gasket knock pin holes too, comes with the aftermarket territory unfortunately. I like to leave the flat o-ring up slightly on the knock pin, then slip the gasket over it (once the holes in the gasket are large enough to freely fit) so a little of the o-ring protrudes out of the top of the gasket so you know it will contact the head surface and get compressed properly inside the gasket opening. I smear the Hondabond around the holes in the gasket leaving about a 1/4" of space between the sealer and the hole so it can't spooge its way into the opening. And don't forget the narrow areas across the front and rear of the cam chain tunnel. (obviously the gasket picture is flipped left to right)

450 head gasket sealer.png
 
Is that just camera angle that is making the fire ring look like it's protruding into the cylinder?
 
Yes, some of the flat o-ring should stick up inside that hole in the head gasket. I've had to open up some head gasket knock pin holes too, comes with the aftermarket territory unfortunately. I like to leave the flat o-ring up slightly on the knock pin, then slip the gasket over it (once the holes in the gasket are large enough to freely fit) so a little of the o-ring protrudes out of the top of the gasket so you know it will contact the head surface and get compressed properly inside the gasket opening. I smear the Hondabond around the holes in the gasket leaving about a 1/4" of space between the sealer and the hole so it can't spooge its way into the opening. And don't forget the narrow areas across the front and rear of the cam chain tunnel. (obviously the gasket picture is flipped left to right)

View attachment 36764
Thank you and that is what I thought I should do on the seals but wanted to make sure. I am planning on using Hondabond where you have indicated.
 
Is that just camera angle that is making the fire ring look like it's protruding into the cylinder?
Thanks for looking but I believe it is just camera angle and the gasket was not fully seated when I took that photo but I will take an extra look when I get to work on it.
 
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