Bad noise after rebuild

IT IS ALIVE!!!!!! Well kind of...... it wont turn over just spits black smoke. However the starter clutch works!

The pics below are everything I did and will explain them now:
1. just the back side flattened (I need to grind the face of my hammer smooth its pretty pitted haha)
2. All faced hit with a dremel to smooth them, also plunged the holes so the caps can freely compress all the way without hanging on the return. This should be done during the rebuild, every time I would remove the one way bearing there was a least one if not all caps hung in the holes.
3. just another picture of the one way bearing, took a bastard file to the face just to remove any burs.
4. Had my awesome machinist brother groove the face, it is well within service limit. This I think should be mandatory for anyone doing this starter clutch rebuild, I bet you take it to a local machine shop they will do it for darn close to free.
5. All OEM springs, caps, and rollers. Just do it, don't get a rebuild kit just go OEM trust me.
6. This came with the one way bearing from an 84 trx125 (I think thats what it was on), I figure they put it on later models to help the rollers turn smoother then just pressed up against the main sprocket face. Can't hurt and I see it as a good addition.
7. Showing how it looks with the extra piece all together!

That last picture shows assembly on 'backwards' for some reason?
Duh, just realised it's the correct assembly when it's bolted to rotor :-[

crazypj said:

That last picture shows assembly on 'backwards' for some reason?
Duh, just realised it's the correct assembly when it's bolted to rotor :-[

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You had me panicking!!!
Especially cause I was just out there tinkering and it still slaps a bit.

Did you torque the starter clutch mounting screws? I've always found them to be a PITA to get tightened up properly even when held in a bench vice, driver always wants to flop out of screw head ???
At least the torx screws are a little easier than the Phillips they used in earlier models. I almost always grind torx bits flat on the end so they locate better in screw, sometimes the end shape just seems to 'rounded' ;D

crazypj said:

Did you torque the starter clutch mounting screws? I've always found them to be a PITA to get tightened up properly even when held in a bench vice, driver always wants to flop out of screw head ???
At least the torx screws are a little easier than the Phillips they used in earlier models. I almost always grind torx bits flat on the end so they locate better in screw, sometimes the end shape just seems to 'rounded' ;D

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They have to be tightened after everything is installed as far as I can tell

dab o blue will do

Tune-A-Fish said:

dab o blue will do

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Yeah and I realized after all was said and done I had never done it this time around. :-\

I would definitely richen up your jetting a little. Those plugs look a little off. Also, I’m not sure about the flange on the starter clutch gear but there is an mod for the 79-82 cb750 that uses an r6 bearing. Here is the link. https://www.youtube.com/watch?v=sYJSUiXDim8

and here are measurements from the 750 bearing unit that I replaced with the r6. I don’t know if it will work but it may.

esmoojee said:

I would definitely richen up your jetting a little. Those plugs look a little off. Also, I’m not sure about the flange on the starter clutch gear but there is an mod for the 79-82 cb750 that uses an r6 bearing. Here is the link. https://www.youtube.com/watch?v=sYJSUiXDim8

and here are measurements from the 750 bearing unit that I replaced with the r6. I don’t know if it will work but it may.

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Man that would be sweet! However the part numbers don't match up sadly.
Honestly I think the starter clutch will last a while and between now and then I will figure out my next plan of attack. Maybe make a sleeve for the race and do the set up you linked....

However right not I need to figure out this damn black smoke thing so I can at least get it started......I just want to ride it.

To elaborate on the smoking issue in case someone has ideas...

After the second motor rebuild to fix the new oil leak I installed K&N RC-2362 air filters ( http://www.knfilters.com/search/product.aspx?prod=rc-2362 ) to replace my EMGO pod filters. I had re-jetted the carbs to 42/120 and have the screws 1.5 or 2 turns out i cant remember (any recommendations?), float height is stock and needles from the rebuild kit are at the richest position. Also, MAC 4-1 exhaust. The bike ran tolerable just needed some tuning with the pod filters before the rebuild, now after the rebuild it won't even fire up just tries, puffs black smoke and will occasionally do a weird rev-up thing but not actually run. I am assuming cam chain, could this be a symptom of tooth off?

does it run with the choke on? also, where specifically does it smoke from? If it's around the header try tightening the exhaust studs. Mine did that until I tightened them. It also smokes fromt the breather hose filters sometimes until I put a longer hose on it.

esmoojee said:

does it run with the choke on? also, where specifically does it smoke from? If it's around the header try tightening the exhaust studs. Mine did that until I tightened them. It also smokes fromt the breather hose filters sometimes until I put a longer hose on it.

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Smoking out the old tail pipe, choke/nochock makes no difference D I duck with the throttle a bit holding it in just the right spots it tries a little harder but zero success

Okay, lets start with compression. Have you done a compression check since you rebuilt? Look there first. What about the carbs? Gone through everything? Cleaned all passages? Float height good? I think you said in a previous post you have an inline fuel filter. If so, try taking that out and see if it's not suppressing your fuel flow. Run a line without it.

A few other things. Is your timing set? I would also check the coils ohm resistance.

I just looked up your jetting and it seems like your carbs are set up correctly. Check the timing and compression. Did you readjust your valves after rebuild?

Okay, lets start with compression. Have you done a compression check since you rebuilt? Look there first.
I haven't, it ran well with the first rebuild then I took the head off and just did a gasket swap with no other changes, can't really imagine anything going wrong with the rings. I will need to buy a compression tester as I do not have one.

What about the carbs? Gone through everything? Cleaned all passages? Float height good?
Did a full carb rebuild, and ran the bike like that with emgo pod filters for a bit ran well. Everything was cleaned all passages clear, stupid diaphragms all cleaned (no tears and in good shape so I left them alone), floats set at stock hight per recommendations with the intakes / exhaust I was running.

I think you said in a previous post you have an inline fuel filter. If so, try taking that out and see if it's not suppressing your fuel flow. Run a line without it.
I can do this, but I cant really imagine it would work fine with the pods and now not work with the K&Ns. The other thing is it smells really rich but that is probably from turning over constantly and not ever actually running.

A few other things. Is your timing set? I would also check the coils ohm resistance.
Timing was check last night, all good there for a static check.


My thing is, if it all worked before replaced gaskets and now the only change is the K&Ns it should still at least run a bit or come close to running so I figure it can't be in the carbs / sparks.
Maybe I will rip the head off and quadruple check the cam chain timing and post pics of it?

esmoojee said:

I just looked up your jetting and it seems like your carbs are set up correctly. Check the timing and compression. Did you readjust your valves after rebuild?

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Well that is good at least.

I did readjust the valves, I always do when I split the two.

That's strange, you should be fine then. I would definitely check compression when you get the chance. Try setting your needles back down to the middle slot on your carbs. Maybe you're getting too much fuel.

Do you have a #40 jet? Try putting that in as well. Start with your air screws 1.5 out

esmoojee said:

That's strange, you should be fine then. I would definitely check compression when you get the chance. Try setting your needles back down to the middle slot on your carbs. Maybe you're getting too much fuel.

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esmoojee said:

Do you have a #40 jet? Try putting that in as well. Start with your air screws 1.5 out

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Ok, First thing I will look at is cam sproket just to make sure it is correct as that is the only thing I can think could be off between now and pre-re-rebuild.
Then once I can get the sweet moola for a compression tester I will test that and report back.

I will check all the carbs to make sure they are at 1.5 turns too while I am at it. if none of the above works I will redo the needles and get #40 jets.

R6 sprag clutch is a neat trick, pity it wasn't around in the 80's ;D