Russ Collins RC 388 camshaft Identification

The lightened matching cam followers sold. Dang, I wish we had KZB2 650 information sooner, I’d have bought them. Here’s a screenshot. Appears they do not have the oil grove. Must be how the were able to run the SOT.

Mikaw wrote: RC Engineering say it can be used with SOT, but recommended their lightened buckets. That's the way it was set up when Asphalt900 opened it up.

It's probably doable, for as long as your luck holds out. But it seems like you're rolling the dice with shim-over and that much lift. My dad spit a shim out of his Z1 drag bike and it flew out of the head. Fixing that seems like more work that switching to shim-under.

Mikaw wrote: The lightened matching cam followers sold. Dang, I wish we had KZB2 650 information sooner, I’d have bought them.

Kibblewhite and APE sell new shim-under followers. The APE site says "This is a must with cam lifts over .410 in a Kawasaki"

DOHC wrote:

Mikaw wrote: The lightened matching cam followers sold. Dang, I wish we had KZB2 650 information sooner, I’d have bought them.

Kibblewhite and APE sell new shim-under followers. The APE site says "This is a must with cam lifts over .410 in a Kawasaki"

I thought the 650 had SOB followers. Not sure what year but I remember reading that somewhere. And a ton cheaper.

All KZ650 had shim under bucket followers. Bought a cheap KZ650 head on evil bay for 40 Euro to get the SUB followers for my FI conversion winter Project.

Mikaw wrote: I thought the 650 had SOB followers. Not sure what year but I remember reading that somewhere. And a ton cheaper.

Yes, the 650 has shim-under. At least my '77 and '79 did. I'm guessing the 750 did as well?

I've read that they will drop in to the 900/1000 engine. But I've also read that the 650 followers are not strong enough for a high-lift applications with stiffer springs. Maybe someone with experience can comment.

Sorry No info on the duration other than it states 108. ...... and right the lightened followers are only recommended not a must. I remember a thread on here where these were talked about and someone mentioned that the holes weakened them more than they expected and were prone to warping slightly and wearing. If it was true don't know for sure.

The stock KZ650 shim under buckets are only good for up to .370 lift........... that's where Andrews always drew the line on the 650 cams they sold. RC and V & H said the .350 lift was good but the hardened buckets were a must on their .400 grind.

The '83~'84 ZX1100 GPz which has I believe are .385 lift cams uses the same shim bucket as the Kz650/750 4's (12032-1001).

So if Kawasaki uses the Kz650/750 shim bucket with a .385 lift cam, it must be safe to use them at that lift.

I have used the Kz650 retainer (12008-009) with Yoshimura Bonneville (.385 lift) and Super Bonneville (.410lift) cams and never had any problems.

I believe if I remember right even the Factory Superbike the Kz10000S1 used the stock Kz650/750 retainer with around a .400 lift cam.

The Z650/750 - Unitrack 1100 buckets and retainers drop straight in any SOT Z1/1000 engine to convert to under bucket shim.
You don't need them on 410 lift.
The cause of shim spitting is the groove around the top of the bucket under the shim.
It's the sweep of the high lift cam running close to the edge of the shim that rocks the edge of the shim in the groove causing the other side to lift and then possibly spit the shim out like tiddly winks.
If the cams sweep isn't that far or the groove is filled or absent as in the RC ones then there is very little risk at any lift..

zed1015 wrote: The Z650/750 - Unitrack 1100 buckets and retainers drop straight in any SOT Z1/1000 engine to convert to under bucket shim.
You don't need them on 410 lift.
The cause of shim spitting is the groove around the top of the bucket under the shim.
It's the sweep of the high lift cam running close to the edge of the shim that rocks the edge of the shim in the groove causing the other side to lift and then possibly spit the shim out like tiddly winks.
If the cams sweep isn't that far or the groove is filled or absent as in the RC ones then there is very little risk at any lift..

Thanks Zed. Are there are OEM SOT buckets that do not have the oil grove? If not are there any in the aftermarket world?

KZB2 650 wrote: I remember a thread on here where these were talked about and someone mentioned that the holes weakened them more than they expected and were prone to warping slightly and wearing. If it was true don't know for sure.

This was a big reason I didn’t buy them. Asphalt900 mention he thought one or more had warped slightly. He said the were hanging up. But still if I had known that RC recommended them I would have bought them.

Thank You

Mikaw wrote: Thanks Zed. Are there are OEM SOT buckets that do not have the oil grove? If not are there any in the aftermarket world?

I don't know of any stock ones without the groove and all after market ones just cater for the shim under.
I run all mine with shim on top and most have around 410 lift cams Kent and Norris.
I've never had any issues and i rev them hard.