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Machine shops usually have a hot tank for cleaning parts, $100 or so. Automatic transmission shops have a pressure parts washer unit usually.
 

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Discussion Starter · #22 · (Edited)
Machine shops usually have a hot tank for cleaning parts, $100 or so. Automatic transmission shops have a pressure parts washer unit usually.
I got access to a supersonic parts washer that's big enough for the job, but I want to have the old paint removed from the engine. Started with some wire brush attachments on the angle grinder, applied a little paint stripper on the head as a test, going to take some work but I think I can get it cleaned up. Still looking around to see if there is a place that'll soda blast the painted parts for cheapish
 

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Discussion Starter · #23 ·
I've been long overdue for an update, but the project has not sat idle. My goal is to have this bike finished by next February for the 2021 race season, plenty of time to do what I want to it.
I found a guy to soda blast my parts for cheap, it's not a perfect finish but sure beats that old peeling black paint. Spent lots of time cleaning off all the old gaskets, it's ready for reassembly now. Also got my cam and rockers back from Delta cams, I'm pleased with the level of service they provided at such a low cost!
I also got around to fabbing up a new windage tray with some scrap sheet metal.
Here's a few glamor shots of the cleaned up parts!
 

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Discussion Starter · #24 ·
Getting ready to assemble this engine.

After some deliberation and thought, I've decided to take a chance on my cam chain tensioner rollers and cam chain, and reuse them. I have found no information on what the cam chain stretch spec should be, can't seem to find any mention of it in the service manual, and half an hour of searching on the web has yielded no results. My google search game is weak today... but I feel confident that the chain is good for several thousand more miles since there's only 2k-some-odd on the clock.

Cam chain rollers are another story. This I'm slightly concerned about, however I think they are in good enough shape to run, at least until the engine properly grenades itself and I go all out with the another rebuild. They pass a visual inspection, no damage or cracking on the surface of the rollers, and they spin freely. My concern is with the age of the rubber. It is quite hard, I can't even press my fingernail into it. But then, I thought, it probably makes sense that this would be a harder surface, since it is designed for the chain to run over at high speeds.

I've heard and read stories about old cracked rollers coming apart, causing serious engine damage. I know this is a risk, but I figure if it blows up I can build it bigger and better. If you want to convince me otherwise now's your chance!
 

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How does your cam chain look and feel? Some engines have a chain that look and feel fine. Others I've seen the chain has visual wear and the plates feel worn and sometimes sharp.

As for the rollers, it's my understanding that higher rpm beats the brittle rollers harder. They will start to come apart and you will notice your oil gets very dirty very quickly as pieces start to float around in the oil. Some will get caught in the sump screen and some will travel through the system. You will also risk oil supply failure if your screen gets clogged.
Being said, if you don't mind pulling to replace parts (worth case the whole top end valves, pistons, head, camshaft) and dealing with the sudden and unexpected loss of use, then def proceed.
If it sounds unappealing, remember you're only saving $175 USD by not replacing the chain and tensioner system
As a side note, a lot of 350 owners are out there on old parts. You have the opportunity to freshen yours. I had a similar opportunity and chose not to, but I've also now built 2 other engines that have new chain and tensioners, ready to swap in
 

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Discussion Starter · #26 ·
How does your cam chain look and feel? Some engines have a chain that look and feel fine. Others I've seen the chain has visual wear and the plates feel worn and sometimes sharp.

As for the rollers, it's my understanding that higher rpm beats the brittle rollers harder. They will start to come apart and you will notice your oil gets very dirty very quickly as pieces start to float around in the oil. Some will get caught in the sump screen and some will travel through the system. You will also risk oil supply failure if your screen gets clogged.
Being said, if you don't mind pulling to replace parts (worth case the whole top end valves, pistons, head, camshaft) and dealing with the sudden and unexpected loss of use, then def proceed.
If it sounds unappealing, remember you're only saving $175 USD by not replacing the chain and tensioner system
As a side note, a lot of 350 owners are out there on old parts. You have the opportunity to freshen yours. I had a similar opportunity and chose not to, but I've also now built 2 other engines that have new chain and tensioners, ready to swap in
You make good points, after your comments I'm back on the fence about it. The old cam chain is in good shape, if I knew what the spec for it was I would measure it to be sure, but that's a cheap replacement anyway. Cam chain is 50 bucks or so, set of rollers from common motor is 180, but I bet I could find them cheaper. I suppose if I don't replace them now they will have to be replaced in a future engine rebuild anyway.

Thoughts on these steel rollers I found on ebay?
I'd like to get an AK1 tensioner in there but they are no longer available from boretech. Whatever the solution is I hope to get the parts ordered in the next couple days.
 

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I've found the chain on eBay for $20ish. I don't recall now. You need to look it up by the number.

Rollers are like 140. May come with skipper.

I'd go rubber over another material.

Longdistancerider did a build and fair amount of research and exp. check it out for info too
 

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I looked at all the available options on the rollers. I went with the stock rubber versions for 2 reasons. First is the noise factor of metal to metal contact, I'm building a long term rideable street engine and adding the expected whine of the metal rollers isn't what I want. Second and more important is the wear factor. As the maker of the steel rollers mentions he uses chromoly steel so the wear take place on the roller instead of the chain. Steel creates very fine particular debris as it wears that will bypass the pickup screen easily and may be fine enough that at low rpm can bypass the centrifugal oil filter system. It's the consistency of a very fine grinding compound. Rubber tends to create larger fiber debris that will initially lodge in the pickup screen and what makes it to the filter will have enough volume in size to stay in the filter.
Since this is a race engine the noise is of no concern and steel wear issue is minimal since during the regular scheduled teardowns of the engine for freshening will reveal any wear patterns developing and can be corrected. I'm assuming that the engine will be torn down every 3-4 races or at least yearly.
The old KA slipper wasn't a bad idea since there were no wheels involved and the slipper guides were made of Delrin. Too bad they went out of business even with the fitment problems of the design.
An interesting video I watch of a CB350 race engine build had ball bearings used in place of the roller wheels, could see any part numbers on them. They ran a remote oil filter with that engine.
 

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Discussion Starter · #29 ·
I looked at all the available options on the rollers. I went with the stock rubber versions for 2 reasons. First is the noise factor of metal to metal contact, I'm building a long term rideable street engine and adding the expected whine of the metal rollers isn't what I want. Second and more important is the wear factor. As the maker of the steel rollers mentions he uses chromoly steel so the wear take place on the roller instead of the chain. Steel creates very fine particular debris as it wears that will bypass the pickup screen easily and may be fine enough that at low rpm can bypass the centrifugal oil filter system. It's the consistency of a very fine grinding compound. Rubber tends to create larger fiber debris that will initially lodge in the pickup screen and what makes it to the filter will have enough volume in size to stay in the filter.
Since this is a race engine the noise is of no concern and steel wear issue is minimal since during the regular scheduled teardowns of the engine for freshening will reveal any wear patterns developing and can be corrected. I'm assuming that the engine will be torn down every 3-4 races or at least yearly.
The old KA slipper wasn't a bad idea since there were no wheels involved and the slipper guides were made of Delrin. Too bad they went out of business even with the fitment problems of the design.
An interesting video I watch of a CB350 race engine build had ball bearings used in place of the roller wheels, could see any part numbers on them. They ran a remote oil filter with that engine.
LDR you make a good point on the wear of the metal rollers, but as you stated, maintenance on this engine will be much more frequent that on a street bike. Is it perhaps this video you mention? I saw it and was wondering about it as well, interesting design. I don't think it would be terribly difficult to build a homemade roller setup like that.
At least I can put the bottom end back together while I debate which roller setup to go with. I've thought about rigging a remote filter and oil cooler, certainly not out of the question. Time to do some more research...

While I'm not opposed to spending money on this build where it needs it, I'm trying to keep my costs down to around $1k, which I know is pretty slim for a race bike budget, but I think with this class it's very doable. The whole idea was to dip my toes into racing without completely breaking the bank. Fact of the matter is that this won't be a top performance machine, guess that I'll just have to become a better rider to compensate 😜
 

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That's the video I was talking about. You are correct that racing a vehicle with less power than the competition will make a better shoe. When I got involved with a new driver and car I would make sure all the safety equipment was in place and give them race quality brakes and suspension plus a few minor engine upgrades. This taught them how to steer and brake while trying to keep up. Once they were competent with that then we dealt with a serious engine.
 

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I watched that video and looks like the cam chain tensioner bearing came apart. Down in the comments section the poster said there was an issue with it being too rigid.

Edit: I watched the build video by the same user and saw this in the comments, regarding the cam chain tension system. Apparently the bike is from 1995, too?


Terry Threlfall


It looks like you made sleeve adapters to press into the center of a couple of unsealed roller bearings to use in place of the cam chain rollers? what O.D. are the 2 bearings you used? I may do the exact same thing as I cannot find any aftermarket rollers at a reasonable price.


3 years ago














3








linus


Sorry, i don't remember the dimensions for the bearings. However I don't recommend this configuration for street use, make too much noise.


3 years ago




















Terry Threlfall


linus i am looking at a setup on ebay that has solid steel rollers machined to be identical to the factory rubber ones. same price as factory NOS


3 years ago




















linus


My experience original rubber rollers do not survive high rew. Solid steel rolls could be better, but the chain should be replaced.


3 years ago
 

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Discussion Starter · #32 ·
Ended up ordering the metal rollers. I figure with as often as I'll be changing the oil the wear isn't an issue, and neither is the noise factor.

Also got a deal on a 2.15x18 rim off a late 80s xr600 coming for the rear wheel, swapping the stock rear rim to the front.
 

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Discussion Starter · #33 ·
Got a cylinder hone coming, aside from that I have everything to put the engine back together as is. Figuring I still need a good deal of parts to get this thing rolling solidly, including tires, chain and sprockets, a battery, brake shoes, forks and triples, wheel bearings, swing arm bushings, tapered steering head bearings, front fender, and a couple pipes. I'm about to blow over my original budget number. definitely going wayyyyy over at this point, but hey, it's hard to not do things right once you start taking them apart.
I went ahead and changed the color of my "TOTAL" number on my costs spreadsheet to white so I can't see it, we'll see what that number is once the build is completed 🤑:ROFLMAO:
307860
 

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Discussion Starter · #36 · (Edited)
It has been a busy summer for me despite everything being shut down, and I haven't had a ton of time to dedicate to this build or the log.
But now I have no excuse, I'm forced to stay in bed due to a broken leg, and have ample time to get caught up.

While being unable to walk sucks, I'm taking this time to really crack down and get some research done and parts ordered. I've set a hard deadline to complete the project by early February, in time for the race at Roebling. I'm hoping to get a lot of work done over the winter months while things are slow over at the shop. Gonna hit the ground running as soon as I'm back on two feet!

Since the last update, I've gotten the engine to a point where it can be installed back in the frame. I'm a fan of mounting an engine in the most disassembled state, it's a little easier on the back that way 👌

The case halves are mated- then I cleaned everything, honed the cylinders, installed new rings and pistons, lapped the valves, rebuilt the cam chain rollers, set valve lash, and hung the engine in the frame. Still need to bolt everything else on the right and left side though 😅


Now I'm changing focus and working on the chassis. I removed the swingwarm and gave the frame a good clean. It's nowhere near perfect, lots of small little spots of surface rust, chipped and dinged up paint, but otherwise totally solid and functional. I may touch it up a bit with some fresh paint, but I don't feel like spending more dough getting it powder coated.

The swingarm bushings are actually in really good shape, finally one thing I won't have to replace! Just cleaned all the old grease out, slapped on a little fresh grease and reassembled, good to go.

Definitely need to source some new shocks though, I'm open to suggestions. Only limitation is that they need to be straight body.

I laced up the rear wheel with an old 2.15 xr600 rim that I picked up for cheap, pretty happy with how that turned out! Still need to figure out the sprocket gearing, I think I'll ride it around on the sprockets that came on it first just to get a baseline.

I'll reuse the 1.85 rear rim and lace up the front wheel with it eventually. I've found a decent set of late model cb350 forks with the yokes for about 100 bucks shipped, I think I'll go ahead and get that coming to beef up the front end a bit. If I'm not mistaken my wheel should bolt up fine to these:
Honda CB350 Twin '68-'73 Front Forks, Triple Clamp, CL350 | eBay
Then I'll just throw in some proper springs and maybe a gold valve emulator- not sure if there is much else I can do for the front end without cheating. The wording in the rules says that I can use any set of period correct forks and wheels, but need to use OEM clamps.

Sooooo that's about all the progress I got in 6 months! It has been a slow process, chipping away at it here and there, but now it is finally starting to look like a bike again! My enthusiasm for the project is getting a much needed second wind.

Hoping to get back on two feet in a couple weeks, in the meantime I would appreciate any input on what I should do about the suspension!
 

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Discussion Starter · #37 ·
Last were befores, here are some afters:
 

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