71K0 just brought out of a LOOONNGG storage.

[cjpayne]

Are you using a digital ohm meter or an analog meter? Hopefully you have a DVM for this check.

Thanks for the values. I usually use an analog DeArsnavol meter movement on these bikes, but I do have a DVM for a backup.

 

[cjpayne]

BTW CJ, feel free to take a few pics and do a how-to thread on the subject :becky:

Great idea kirrbby, but my camera doesn't really ever get a good pic of the tiny meter needle. Besides, I barely had any sleep the past couple nights and took a LONG nap after work today.lol. Just doesn't sound good right now.

 

[cjpayne]

i think I read this right, but don't take a good running bike apart to try fix another one. I think you were thinking about taking the stator off one to put on another.
Just never a good idea, something breaks, or gets stripped out. Just my opinion.

I get your point and it's a good one. I usually do things like that when I get desperate for answers. It's great when you have another bike to test parts out on and is a valuable asset to have when needed.

 

[kirrbby]

Great idea kirrbby, but my camera doesn't really ever get a good pic of the tiny meter needle. Besides, I barely had any sleep the past couple nights and took a LONG nap after work today.lol. Just doesn't sound good right now.

Next time I have the need, I'll maybe start a thread so I can learn how to check these the right way once and for all. Dumb it down enough so even I can follow it.

Glad you found the problem. You must be gettin close.?

 

[cjpayne]

I hope you dumb it down, so I can follow too. Alot of times I need foolproof(foolproof points?).lol.

Yes, it's getting close. Still have to do alot of tiny stuff, but I should have this thing running when I get a free afternoon or two.

 

[69ST]

I finally found the problem. Boy did I feel like a dumbass!!!lol. Was OHM probing around as Bob suggested and came across something unusual. The lead going to the points was not conducting TO the points contact. I soon realized that I had placed the lead in between the insulator and the body of the points bracket, not between the insulator and metal washer. I corrected this and I got tons of spark. This pic is crappy, but look close and you'll see the mistake.

View attachment 29602

I then unhooked my makeshift HTcoil and rehotwired the original. It works.

First off, congrats...that's gotta make your day. Second, it's almost always simple things that are easily corrected, in minutes...after spending hours tracking them down in the first place. The bad news is that visual acuity isn't known to improve with age. The good news is that cheater glasses are cheap and make life a lot easier when dealing with tiny stuff like this. The better news is that having now passed another exam in the DIY mechanics school of hard knocks you're just that much more capable for next time.

 

[cjpayne]

Good news and bad news.
Good news is bike is pretty much complete. I was thrilled to hear it run finally.



The bad news is that I took it for a test drive. 1st and 2nd are fine, but when I put it in 3rd, it makes this rapid clunking sound. It almost sounds like CS is wore out and the chain is binding, but it only does this in 3rd gear. I reused the sprockets and a used chain I had. They are a little wore. I was going to get some new ones later. I thought I had a new chain, but didn't. The back sprocket is an aftermarket 36 that still looks pretty new. I guess I'm gonna have to remove the flywheel cover and chainguard, then drive it in 3rd to see where the noise is coming from. I'm hoping it's not the tranny.:42:ray:

 

[69ST]

More bad news, I'm afraid, Chett...sounds to me like a missing gear tooth. I've rebuilt a couple of H-motors with one broken 3rd gear tooth. Maybe just a coincidence that it was third gear with both of them. They also had bent shifter shafts, crash damage.

I suppose it could be a chain/sprocket issue. Seized links can manifest as this, chunking only at certain speeds. Pull the chain, check every link. Check the sprockets while you're at it. Might be worth trying another chain, as a test. I'd start with this. If luck is on your side, the ass you end up not kicking (for needlessly splitting the cases) will be your own.

The next test, remove the sparkplug, shift into 3rd, then push the bike. A broken gear tooth will be heard and felt. That's as much as can be done without tearing into the motor. From here, you'll have to pull the clutch and shifter shaft to check straightness. A bend is bad news. Next test is spinning the primary driven gear by hand, while putting load on the C/S. Let's stop here, for the moment. See what you can find the easy way.

 

[kirrbby]

See if it makes the same noise in third when the bike is not moving. I had a H that did that in 1st. Pretty sure it made the noise even when sitting with the clutch disengaged.

 

[cjpayne]

I already put the bike in my small shop and it's started to rain again. Taking the plug out and pushing the bike sounds like the best way to find out. The chain is still pretty oily and loose when I put it on. The CS is wore, but the teeth tips are not sharp and should still last awhile. The clunking does sound like it's coming from the CS area, but I realize that it may just be the harmonics sounding that way because the flywheel cover and chainguard are on.

 

[cjpayne]

See if it makes the same noise in third when the bike is not moving. I had a H that did that in 1st. Pretty sure it made the noise even when sitting with the clutch disengaged.

I'll try that too kirrbby. Thanks

 

[kirrbby]

I'll try that too kirrbby. Thanks

It would rule out the chain/sprocket.

 

[kirrbby]

See if it makes the same noise in third when the bike is not moving. I had a H that did that in 1st. Pretty sure it made the noise even when sitting with the clutch disengaged.

Ya I've realized that would only work if it was first gear and on the mainshaft. But if you just remove the chain you could go thru the gears to rule out the chain and sprockets. Maybe spin the CS by hand with it in 3rd and not running.

 

[cjpayne]

I was thinking and remembered that some months ago I acquired a 6volt Z50 motor from the local MC shop. I'm wondering if it has a good tranny. Since those Z50's are alot easier on the tranny, I'm thinking it probably is in good shape and would make a good donor. Hmmmm........

 

[69ST]

IDK about a Z50 tranny swap...into a CT70H. There's essentially nothing that interchanges so, it's a complete tranny swap. Zs are easier on bottom end parts. They still wear shift forks, a new pair in three-speed flavor is gonna cost a C-note. You'll need a different sprocket combo, for your 3-speed manual setup. This could easily equal the price of a new AHP trans, complete. Knowing that your dedication to OEM, I'd suggest shopping around for a used 3rd gear pair. A buck-fifty ought to buy NOS, so used should come in lower. There may even be a member, or three, with "too much crap":3:, including 4-speed gears.

IMHO, best to find out what's actually gone pear-shaped before prepping for surgery.

 

[cjpayne]

Oh it's not a 4speed, just the usual 3speed. It does have the original engine. I talked to Kevin yesterday about it and what the problem could be. He said that back in the day the bike was wrecked on its left side pretty hard when he and his brother were riding it one day. He also said that he seemed to recall the third gear noise, so I'm kinda relieved that it was nothing I caused.lol. I told him, if it's the tranny gear, that the repair would be a complete teardown and that I have torn motors completely down, but never put them back together. This original engine is not really something I want to learn on.....if ya know what I mean. The bike runs and drives fine, but sounds like hell. The carb seems to work flawlessly and is in very good shape. I will be talking with Kevin later since were still "on the fence" about what to do next.

 

[69ST]

I wasn't aware that it was a 3-speed. In that case, the Z50 tranny is completely interchangeable, not to mention cheap...since you already have it.

The only painful part of this is the required teardown. One hates to split the cases on a solid, healthy, good-running engine, because it's a can of worms. The rings are fully seated, the original crosshatching probably a memory. It is possible...just barely...to leave the piston inside the bore and the rings undisturbed. But, keeping everything completely free of all traces of dirt, throughout the process, not so much. That's where things get messy, literally & figuratively.:40:

The clutch-side cylinder studs can be removed from the case half, the flywheel side loosened, then the cylinder lifted just enough to pull the clutch side case half away from the tranny & crank. Unfortunately, I can all but guarantee you that every gasket is going to tear apart, leaving pieces stuck to every mating surface. I'd plan on doing a complete teardown, just to properly clean everything. It'll be impossible to remove all traces of the old gaskets otherwise. The cylinder base gasket is always the worst.

That's the bad news. The good news is that the cylinder walls & piston are probably in nice condition. So, deglazing the cylinder and installing new rings should be all that needs special attention, beyond the primary task of replacing a gap-toothed 3rd gear. I'd leave the cylinder head alone, unless the intake port is blackened...which I doubt.

 

[CTKing]

Did you try unscrewing the spark plug wire cap. Sometimes they get a bit corroded and you will lose spark. I have had this happen. I just trimmed the wire back a 1/4 of an inch and them screwed the cap back on. Put it back over the plug and the spark was sparking away.

 

[cjpayne]

Yo kirrbby. Please hang on to the 4speed tranny set up. He sincerely wants it after finally seeing/riding the bike. When he saw the bike, he was VERY happy with the way it looked. After adding up the new OEM and used parts that were put on the bike, it was well over 400. PM, text me, or respond here(would be easier). Thanks

 

[kirrbby]

You got it CJ. They're not goin anywhere. And you know, if you're vouchin for him, his credit is good here too. Good to hear he likes his new old bike. Are you gonna put the 4 speed in his motor or into your spare? His I'm guessin, since that's the one that's chunkin.