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[PeteF]

Stinkwheel, you're not assuming the snail cams are the same both sides are you?
In all the REs I've had my hands on they are not.

[stinkwheel]

Stinkwheel, you're not assuming the snail cams are the same both sides are you?
In all the REs I've had my hands on they are not.

No more than I assume the front and rear wheels are directly in line with one another or in the middle of the bike. I generally settle for paralell.

[Cranky]

The brake cam is not a snail cam.

[stinkwheel]

The brake cam is not a snail cam.

No, but the ones that set the wheel alignment are.

[dalgrae]

Hi ,in reading this topic,I have a Crusader and looking at both parts books for this and the Bullet,my opinion is that as the rear hub/sprocket assembly can be left fixed to the swing arm ,I fail to see how the snail cams can have a great effect on alingment,they can only exert a force to stop the wheel moving forward,if the sprocket /hub nut is tight no way can a snail cam move this on the opposite side.I am sure this will bring a raft of disagreement ,but that is my opinion

[Wheaters]

There is a limited amount of flex between the swing arm components. The two arms can move in relation to each other and pressure exerted on the rear wheel allows some movement at the snail cams.

My Bullet seems to have a slight angular difference between the left side plate where the axle fits and the fore/aft line up of the tubular arm itself as if the welding jig wasn’t quite accurate enough. To get the wheels in line I have to put pressure on the 3 o’clock position of the rim when standing on the right side of the bike, to pull the axle forward on that side. I check the line up using a straight edged wooden plank with a section of the side cut away to clear the centre stand.

My old BSA was even more out of line, when the axle was tight the top of the rear wheel leaned over to the right. Neither plate was truly vertical in the tubular arms.

[stinkwheel]

Hi ,in reading this topic,I have a Crusader and looking at both parts books for this and the Bullet,my opinion is that as the rear hub/sprocket assembly can be left fixed to the swing arm ,I fail to see how the snail cams can have a great effect on alingment,they can only exert a force to stop the wheel moving forward,if the sprocket /hub nut is tight no way can a snail cam move this on the opposite side.I am sure this will bring a raft of disagreement ,but that is my opinion

You misunderstand what I was proposing to do. If I bolt up the rear hub so the brake drum is aligned with the shoes, then put the axle through and push/pull the wheel so it's square in the bike and tighten the axle, it might pull the drum and wheel out of alignment again.

So if it lands up like this (exaggerated), what effect would applying the brake have on the alignment of the hub relative to the wheel? Would it try to pull the hub square with the swingarm instead of the wheel?


So I was going to try bolting it all up holding the brake on but leaving the snail cams disengaged so the wheel naturally aligns itself with the hub as it's tightened down rather than setting the snail cam position for my perception of when the wheel is square in the bike. See if that movement of the hub relative to the wheel when the brake is applied goes away.

I'm not proposing to ride the bike like that, just to see what happens.

[Cranky]

Crikey what going on here. The snail cams are there to align the wheel. You count the bumps on each cam and make then equal. Then you move each one at the same amount to get the correct chain tension then tighten up. The cams are an aid to alignment. If you are still out of alignment then you have problems with swing arm or its bearings or your bike is twisted.

[PeteF]

Crikey what going on here. The snail cams are there to align the wheel. You count the bumps on each cam and make then equal. Then you move each one at the same amount to get the correct chain tension then tighten up. The cams are an aid to alignment. If you are still out of alignment then you have problems with swing arm or its bearings or your bike is twisted.

Trouble is Cranky, Royal Enfield manufacturing tolerances are not of the best and on all the bikes I've had my hands on the swing arm/frame is not accurately fabricated.
If you set the snail cams to the same number of "bumps" on each side the wheel will NOT be square in the bike.
I've had them one and two "bumps" out (I suppose some of them must be correct)
This is the case with new bikes, not just old worn ones.
The snail cam system is pretty crude anyway as there is quite a difference between one bump and the next.
A screw adjustment system as seen on most bikes would be better and indeed, Mr H sells one.
I think Stinkwheel's last post could quite easily explain the OP's problem.

[stinkwheel]

If you are still out of alignment then you have problems with swing arm or its bearings or your bike is twisted.

Exactly. And I think that is highly likely to be the case. I know for a certainty both wheels aren't directly in line with one another anyway. Probably not enough to go to the effort of re-dishing the wheels. I'm also pretty sure neither is perfectly in the centre of the bike although I haven't ever chalked that out.

There is certainly something slightly off-kilter between the alignment of the brake-drum/shoes and the alignment of the wheel on both of my bullets. That's obvious when you look at the movement round the horizontal axis when you apply the brake. It would probably explain the propensity to lock-up the rear unexpectedly from time-to-time. Then it comes down to finding what exactly is off and if there is a compromise position or and engineering solution. My feeling is still that a more ridgid brake plate would do the trick.

You can't even take the snail cam through its full range of rotation on my 350 bullet on the right hand side because it comes up against the shock mount. Not the case on the left, which should tell you a lot about the degree of precision in manufacture of either the cam, the swingarm or both...