1971 CB350 . . . 40 year hibernation

[Cycleranger]

That looks about right!

There's no D washers on the 360.

 

[ballbearian]

Glad you have the later triple crowns that weren't susceptible to breaking. The older ones that broke and needed the D washers did not have that V shaped clearance area where the pinch bolts go through. I can get some pics from my stash of two broke ones and one that may have a slight hairline fracture. D washers can't hurt though but aren't needed.

I didn't realize the new bearing set came with a top rubber seal too.

 

[Cycleranger]

I would use a bit more grease on that bearing. It looks a bit dry.
Really pack the grease into the bearings.

 

[ballbearian]

If there is only one seal, wouldn't it be on the bottom? That's the original way due to most contamination on the bottom. Yeah, pack it full and force the grease into all the spaces in the caged rollers with your palm and fingers.

 

[Cycleranger]

There's a seal on the bottom as well.

 

[stl360+450]

I would use a bit more grease on that bearing. It looks a bit dry.
Really pack the grease into the bearings.

Will do. Thanks for pointing that out.

If there is only one seal, wouldn't it be on the bottom? That's the original way due to most contamination on the bottom. Yeah, pack it full and force the grease into all the spaces in the caged rollers with your palm and fingers.

The kit did include both lower and upper seals, as Cycleranger mentioned. The top seal does seem somewhat less important since it's already covered by the head nut and bridge, but I guess it helps keep the grease where it's supposed to be when everything is tightened up.

 

[stl360+450]

The subject of the offset drive gears on the 350 motor came up earlier in the thread and Jim, AD, and others had explained how it is related to noise reduction, which I find very cool. I wondered if this would be mentioned in the Cycle World Road Test article and ordered a copy of the April 1969 issue to find out. I have purchased similar back issues for my CB360, CB450, and XL350. They make for fun reading.

Anyways, I received the magazine today and the article had this to say about the offset drive gears:

Power is taken from the engine in a rather novel way. The gears are straight cut, a feature which is most efficient, but is noisier than the alternate less efficient method of using helical gears. However, the drive gear on the 350 is actually two rows of gears, the teeth on one row staggered in between the relative position of the teeth on the second row. The power is picked up by two rows of teeth on the clutch shell disposed in corresponding alternation. The effective time the gears are in mesh is doubled — the same factor which makes helical gears silent — while avoiding the power robbing side loading of a helical gear. (HONDA CL350 SCRAMBLER: Meet Son of Superhawk, A Silly 20 Centimeters Bigger, and Even Better, Cycle World, April 1969)

I guess Jim, AD, and others were reading those issues as they came out and holding on to all of these golden nuggets. Meanwhile, I was -4 years old, i.e., not born yet.

 

[ancientdad]

I guess Jim, AD, and others were reading those issues as they came out and holding on to all of these golden nuggets. Meanwhile, I was -4 years old, i.e., not born yet.

Yes, I did get many tidbits of information from reading bike magazines back when they were more technical and less profit-oriented.

 

[LongDistanceRider]

I guess Jim, AD, and others were reading those issues as they came out and holding on to all of these golden nuggets. Meanwhile, I was -4 years old, i.e., not born yet.

Another example of why we, the forum, exist. Information that's lost to time or never published that's been stored in our heads forever. Us older guys learned a good bit from the previous generations and it's our turn to pass along what we know so it isn't all lost.

 

[ancientdad]

Another example of why we, the forum, exist. Information that's lost to time or never published that's been stored in our heads forever. Us older guys learned a good bit from the previous generations and it's our turn to pass along what we know so it isn't all lost.

Absolutely agree, and the primary reason we broke away and started VHT in the first place - because we saw the community value and legacy information being treated only like profit opportunity, and that's not what we were all about then, or now.

 

[ballbearian]

The subject of the offset drive gears on the 350 motor came up earlier in the thread and Jim, AD, and others had explained how it is related to noise reduction, which I find very cool. I wondered if this would be mentioned in the Cycle World Road Test article and ordered a copy of the April 1969 issue to find out. I have purchased similar back issues for my CB360, CB450, and XL350. They make for fun reading.

Anyways, I received the magazine today and the article had this to say about the offset drive gears:



I guess Jim, AD, and others were reading those issues as they came out and holding on to all of these golden nuggets. Meanwhile, I was -4 years old, i.e., not born yet.

Great post Brody. I probably read that when I was 12. This forum is great for people, it always comes down to people.

 

[stl360+450]

This forum is great for people, it always comes down to people.

Agreed. Can't have a forum without people.

 

[ancientdad]

Agreed. Can't have a forum without people.

And even better with GOOD people. And fortunately, we have a pretty good assortment of them (aside from me, but I'll do in a pinch).

 

[stl360+450]

The project is now in the garage. I installed the center stand and would already have the forks on, but one of the forks has an issue. As a reminder, the front end is going to be a mish-mash of CB/CL360 parts acquired from several sources. I noticed something off when I took that tube apart and was hoping it would work properly once assembled, but it was a no-go. The lower tube would not rotate freely of the upper tube and it was actually difficult to remove the spring when I took the top cap out. I'm hoping the [powder coated] lower tube is still usable and am planning to acquire a donor fork to scavenge the remaining parts from.

 

[stl360+450]

I think I am going to have to do a do-over with my fork tubes. They came from a CB360 and I had the lower tubes powder coated. During the disassembly, one of the oil lock pieces separated into two pieces. I hoped that it would all go together during reassembly, but the upper part of that lock piece got stuck in the upper tube and this prevented the upper and lower tubes from rotating freely with respect to one another. I took it all apart and the lower part of the lock piece seems to be stuck in the bottom of the lower tube and I have failed thus far in removing it. I now have a set of donor forks to scavenge parts from, but the upper tubes have more pitting than I'd like and I can't reuse my powder coated lower tube unless I can get that stuck piece out.

Another curiosity is the fact that the damaged lock piece seems to be aluminum, while the one I pulled out of my recently purchased forks seems to be steel (it is at least magnetic). The aluminum one was mangled while I was getting it unstuck from the upper fork tube. Now I'm planning to find and rebuild another set of 360 forks that look better than the ones I have. I'm going to make sure I use the steel oil lock pieces.

 

[stl360+450]

I notice that new aftermarket fork tubes are available from 2fastmoto. This could be a good solution for me. How hard is it to separate part no. 6 from part no. 12?

 

[LongDistanceRider]

Once you remove bolt #19 then #12 should just fall out once upside down. Don't lose #7 the top out spring when 12 falls out

 

[stl360+450]

Once you remove bolt #19 then #12 should just fall out once upside down. Don't lose #7 the top out spring when 12 falls out

Thanks, Jim! That should be easy then — great! What is #11? Washer or spacer of some sort?

 

[stl360+450]

Okay, that was easy. And now I can swap the upper tubes I had before with the new lower tubes, so no need to buy anything except maybe another set of fork seals.

So I have two complete sets of 360 forks. The springs in one set have many more coils than the other. Does anyone know the difference between the two? My guess is one set comes from a CL and the other a CB, but I'm not sure which would be which. Maybe the one with more coils is the CB spring??

 

[ancientdad]

Okay, that was easy. And now I can swap the upper tubes I had before with the new lower tubes, so no need to buy anything except maybe another set of fork seals.

What is #11? Washer or spacer of some sort?

The arrow is pointing to #11, it's like a little piston ring IIRC

 

[stl360+450]

The arrow is pointing to #11, it's like a little piston ring IIRC

You're absolutely right — once I had it apart and could see it, I realized what it was. From the exploded view it seemed like something that could fall out on its own.

 

[ancientdad]

You're absolutely right — once I had it apart and could see it, I realized what it was. From the exploded view it seemed like something that could fall out on its own.

And that's a great example of what I mentioned before about the sidestand spring view, sometimes it helps and sometimes not. I just couldn't remember the exact relationship until I saw the pic, it's been 6 years since I last saw the internals of my 450 forks.

 

[stl360+450]

And that's a great example of what I mentioned before about the sidestand spring view, sometimes it helps and sometimes not. I just couldn't remember the exact relationship until I saw the pic, it's been 6 years since I last saw the internals of my 450 forks.

And I've probably replaced fork seals on half a dozen sets without ever removing those parts from the upper tube, until today.

 

[ancientdad]

And I've probably replaced fork seals on hand a dozen sets without ever removing those parts from the upper tube, until today.

I had mine fully apart then too because the rest of the bike was, but to me it's more of a 'when you rebuild them' thing unless you have the bike for 20 years and never change the fork fluid.

 

[stl360+450]

I am working on putting together one set of usable forks for this project. The first set of donors came from the local salvage yard and were labeled CB360 and I had the lower fork tubes (legs) powder coated. One of the oil lock pieces came apart on the left side and part of it is stuck in the bottom of the lower tube — my efforts to remove it thus far have failed. I have another set of forks that were advertised as 1974 CL360 forks on eBay. I'm planning to use the lower tubes from the CL forks with the CL springs and the CB upper tubes (based on condition). The strange thing I noticed today is that the lower tubes are different in length. The shorter tubes match those on my 1974 CB360G and I can't figure out what model (360?) uses the longer version. The two sets of forks have different springs and the oil lock pieces were substantially different, as noted in an earlier post.

 

[ancientdad]

That's a tough one, and with no part number to differentiate as well as them having the same design and mounting bosses, it would be hard to know for sure. Hopefully someone here will recognize and let you know

 

[stl360+450]

That's a tough one, and with no part number to differentiate as well as them having the same design and mounting bosses, it would be hard to know for sure. Hopefully someone here will recognize and let you know

I was relieved to see that the mounting bosses match. I think it should all work out when I cobble them together.

Looking at Baralahy's recently posted picture (thread link) of the CJ360 makes me think that could be the answer. I had discovered a different part number for that model earlier.

 

[ancientdad]

But it's going to look funny with the top of one lower leg taller than the other regardless how the fender fits.

 

[Cycleranger]

The lower on my CJ is approximately 13 inches from the top down to the axle.
I suspect the reason for the different part number is the CJ lowers were painted black from the factory.
I don't have a CB360 to measure but I see no reason the CJ would be any different size.

 

[stl360+450]

But it's going to look funny with the top of one lower leg taller than the other regardless how the fender fits.

I'm not that crazy, Tom! I have two of each, so I'm planning to go with the shorter ones now on both sides. No powder coat. But I'm stealing the upper tubes from the first set because the others are heavily pitted.

The lower on my CJ is approximately 13 inches from the top down to the axle.
I suspect the reason for the different part number is the CJ lowers were painted black from the factory.
I don't have a CB360 to measure but I see no reason the CJ would be any different size.

The shorter one matches my CB360G and I just confirmed your number for the longer one, with the shorter one about two inches less. Thanks for checking that for me!

 

[ancientdad]

I'm not that crazy, Tom!

Whew... actually, I'd forgotten you had a pair of forks to work with!

 

[ballbearian]

This kind of info on fork tubes, lowers, etc. with lengths and dimensions for 350/360 would be a great archive in a sticky.

 

[stl360+450]

This kind of info on fork tubes, lowers, etc. with lengths and dimensions for 350/360 would be a great archive in a sticky.

Agreed. There's a lot to it. I noticed the oil lock pieces changed with the CJ360 also.

 

[ancientdad]

Agreed. There's a lot to it. I noticed the oil lock pieces changed with the CJ360 also.

I agree too, but it would have to be someone in possession of both sets since comparing parts and part numbers won't tell us what we want to know.

 

[stl360+450]

I agree too, but it would have to be someone in possession of both sets since comparing parts and part numbers won't tell us what we want to know.

I'm happy to document the variations I have. Aside from some subtle casting changes, the main difference between these two is in length. I'll get better measurements and report back with pictures of internal differences. I can also compare with the CB350 K3 forks, which are another animal altogether.

 

[ancientdad]

I'm happy to document the variations I have. Aside from some subtle casting changes, the main difference between these two is in length. I'll get better measurements and report back with pictures of internal differences. I can also compare with the CB350 K3 forks, which are another animal altogether.

Probably no need to bother with the older external spring forks since few would want to do a swap from either of the later style with those, but the comparisons of the later 350 and 360 forks would be awesome (and once again I forgot you have both, times 2 in one case duh)

 

[stl360+450]

Probably no need to bother with the older external spring forks since few would want to do a swap from either of the later style with those, but the comparisons of the later 350 and 360 forks would be awesome (and once again I forgot you have both, times 2 in one case duh)

I didn't even know myself until they were sitting right next to each other and I saw the difference! If I remember correctly, ballbearian has the later style 350 forks, so we should be able to piece things together for at least three different versions.

 

[ballbearian]

Be glad to measure mine when I get to it.
Just looked at franksforks.com but no info on lengths available, only that 33mm is the common diameter for these all.

 

[stl360+450]

Further confirmation of the longer fork legs' provenance. This is the photo I took after bringing them home from the salvage yard. They were tagged '76 and were painted black.

 

[Cycleranger]

Those look like CJ360T forks to me. The reflector brackets look like CJ brackets, they're different than on CB's.
Also the bracket for the drum brake hub.
(And the lowers are black, but they could have been painted by an owner.)

 

[ballbearian]

Here are my '73 CL350 K5 forks. The pic is hard to see the middle and top but the lowers are 12" and the overall is 27.5" from center of axle to top of tube (not the cap nut)

 

[stl360+450]

I did some research on the parts fiches to document the essential differences between the CB/CL360 forks and the CJ360 forks. All of these models use the same upper fork pipe. The internal components of all CB/CL360 forks are identical, but the CJ360 uses some different internal parts, as shown below.

​

Some of the following pictures appeared earlier in this thread, but I am collecting them here for ease of reference.

• The CJ360 lower fork legs are longer than those used on the CB/CL360 models.

• The oil lock pieces on the CJ360 are aluminum while the CB/CL360 pieces are steel.

• The bottom pipes (pipe comp., seat) for the CJ360 forks are longer, but have a shorter head.

 

[stl360+450]

I finally have forks installed on the CB350 project. I used the a pair of CJ360 upper pipes with the lower legs and internal components from a CL360. The CL360 lower legs had a fair amount of corrosion, so I painted them using the same color that I used for the tank and side covers. I also gave them a coat of Spraymax 2K Clear Glamour to help protect the paint.

When I went to install the forks in the steering stem and top bridge, I found it was difficult to get one of the tubes into the top bridge. It turned out to be a small bit of what looked like epoxy (JB Weld?) on the inner diameter of the top bridge. It was resistant to a pick and razor blade, so I used a little flap wheel attachment on my Dremel to gently clean up the surface and the rest of the installation went smoothly.

I plan to install the swingarm as soon as the two recently ordered rubber dust seals arrive. Then I will add the wheels and handlebar and I should be able to move the thing around in my garage!

 

[Cycleranger]

Interesting. I wonder why Honda made those changes to the forks.
You would assume on what was supposed to be a "budget" bike they would use existing parts.

 

[stl360+450]

Interesting. I wonder why Honda made those changes to the forks.
You would assume on what was supposed to be a "budget" bike they would use existing parts.

It seems that the aluminum lock pieces are inferior (probably cheaper, too) to the previously used steel parts, but I agree that it seems weird to retool unless the CJ360 components are also used in some other models.

Looking at CMSNL again, the lower fork legs seem to be used on only 4 models, while the lower pipes are used on 33 models and the oil lock pieces on 238 models.

 

[ballbearian]

Interesting. I wonder why Honda made those changes to the forks.
You would assume on what was supposed to be a "budget" bike they would use existing parts.

It is interesting and we may never know due to some 'secret' subcontractor arrangements and concessions.

 

[ballbearian]

Glad to hear you're making progress Broddy. Thanks for pulling together all the comparison info.

 

[stl360+450]

Glad to hear you're making progress Brody. Thanks for pulling together all the comparison info.

Thanks, Tom. I have less wrench time now than in the summer, but am trying to check something off the list whenever I get the chance. The forks took longer to get right than I expected, but I guess that's a risk when pulling together parts from many sources.

 

[wentwest]

You're going to be the reigning expert on 360 forks. Congratulations!

 

[ballbearian]

Thanks, Tom. I have less wrench time now than in the summer, but am trying to check something off the list whenever I get the chance. The forks took longer to get right than I expected, but I guess that's a risk when pulling together parts from many sources.

I know you'll take the time to do it right.