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I have an All Balls 6905 on the order arriving next week. I’ll wait and compare. I am just not convince of the seal on the replacement bearing…but there is no way this engine is not back together next week!

Yeah that bearing is more than enough for what you need. It doesn’t even do one full revolution once it’s installed! All Balls are Chinese junk, I’d run a name brand bearing with fewer rollers over that crap any day.

FAG is a good German brand. The -2RS designation means 2 rubber seals. You can just pull one out no problem. It’s bathed in transmission oil anyways.

Not every bearing is about rotational speed and this bearing is one of them. It's about the load the bearing has to hold. If the FAG bearing meets the load requirements then run it. However, being 12 balls vs 13, I suspect it will be a lower load rating.

Hello all.
Finally had the time to work on the engine. I got all bearing in the right case half. All went in very easy using the same method as for the left half.
I then wanted to try the transmission before bonding the two halves together. So, without the crankshaft, I did put the gears in with the forks and the shift drum. I secured the two halves together with 4 bolts and installed the shift star, the small lever beside it and the shift shaft with the shift lever to be able to test. I was able to shift to a couple of gears back and forth but definitely not all gears and I was not able to find neutral. I am suspecting I had the shift drum not well aligned. Any ideas?
I am dumb enough that I did not even take a picture of the drum alignment when I removed it! Is there a way it should be oriented? I’ve read and seen on videos you can’t really mess it up (probably why I did not take a picture).
Or maybe my way of testing it is not good.

It only goes together one way. I suspect your testing method could be the issue. The transmission kind of gets in a kink so to say if everything is not aligned well, making gear shift testing cantankerous. Spin the engine with the shaft the clutch mounts to and just keep spinning & working the shift lever.

Picture is worth a thousand words.

Did you rotate the output shaft while trying to shift through the gears?

Is there anyone here who can shift his bike from lowest gear to highest gear without rocking the bike forward and backward a foot or so? I have to on all of my dirt bikes.

I am thinking the same on the output shaft not being rotated.

Yes I was rotating the shaft. Maybe not enough!?! It is not that easy with the engine base on wood blocks to rotate the shaft at the same time you shift with one hand. I’ll try when I get the chance with a third hand. However, your feedback tends to confirm there is no wrong way of putting it together. Chances are it is ok but just not tested the right way.

You’re overthinking it. Just build it and ride

Slick_Nick wrote: 07:38 am May 24 2022 You’re overthinking it. Just build it and ride

yeah I know. Out of town now…when I get back home I hope I’ll have the time to finalize this engine to run it someday!

We are here to help.

Hello all,
Progress update, finally had the time to work on it yesterday. I could confirm the transmission works well. So I started to reassemble the bottom. The crankshaft went in easily in the right half using the heat and freeze method and I did use a crank installer tool like shown in a thread somewhere on this forum. It went straight.
Now I think I will put the piston, cylinder and kips back on and finalize all the right side, clutch and magneto after the engine is on the bike. Kinda hard to tight these bolts when the engine is loose on the workbench. Good idea? How did you do?

KrispyKDX wrote: 08:45 am Jun 13 2022 Hello all,
Progress update, finally had the time to work on it yesterday. I could confirm the transmission works well. So I started to reassemble the bottom. The crankshaft went in easily in the right half using the heat and freeze method and I did use a crank installer tool like shown in a thread somewhere on this forum. It went straight.
Now I think I will put the piston, cylinder and kips back on and finalize all the right side, clutch and magneto after the engine is on the bike. Kinda hard to tight these bolts when the engine is loose on the workbench. Good idea? How did you do?

I built an engine stand out of some aluminum, you could use steel or whatever is laying around the shop.

You can use a penny between the primary gear and the clutch hub gear to lock the engine.

John_S wrote: 11:47 am Jun 13 2022 You can use a penny between the primary gear and the clutch hub gear to lock the engine.

This great advice & how I always do it.

Yeah my problem is not much how to lock the engine. I do this with a rag but the penny is also a good trick but it is more about holding the whole bottom end on the work bench trying to tight at (don’t remember exactly) around 60 ft-lbs.

Update: engine is completed and it did run today. It’s been a long journey… waited forever for parts and I don’t have a lot of time to work on it on weekends. This engine was fully rebuilt with all oem parts except for one bearing (shift drum) which is no longer available. I broke the magneto cover. Manual is wrong about torque spec on this one. I knew it was not possible to torque this plastic cover at what the called for! (87 in-lb).
I still have one problem with the clutch though. I did not replace anything on that clutch but after I reinstalled it, the lever is loose. I did some cable adjustments but it is still loose like. The clutch arm was hard at first but after one shot at the lever, it became loose. Something is not right there. I will start another thread about my problem to document it.
Anyway guys thanks for the help with the rebuild!

Not that it matters now but I thought where you were trying to get the shift drum bearing was out of stock. Not that it was unavailable. I just ordered all the OEM bearings and seals for a bottom end rebuild and that bearing was available in stock OEM at RMATV.

I wouldn't put too much thought into what the clutch issue is. Just pull it back apart and start over. Reading others posts on clutch issues, typically its a just a small oversight in putting it back together that's causing the problem.

Good to know for the bearing. Maybe it is because I am in Canada!?! Not the same thing here for parts I tell you!
I did start another thread to discuss the clutch issue I have…let see how it goes.