RD400 Rear Axle Nut

[RDFL]

As for thickness I have some loose ones somewhere will have to look, wouldn't think could be much if any difference but if is could explain your problem.

[forexer]

Perhaps you're right the bigger hole adjuster maybe allowing just enough slop where the axle becomes crooked when torqued. I guess the only way to know for sure would be to buy another adjuster - one with a small hole for the left side and see if it makes a difference.

Please let me know what you find out when measuring the thicknesses and thanks again for your input 

[RDFL]

They are same thickness.

[1976RD400C]

If you have an adjuster with a big hole where the small hole one should be how do you make sure the wheel alignment is correct because the marks on the adjuster and swing arm will be off?

[Striker1423]

You don't. Swap the adjuster to the correct one as it will allow the axle to travel around. No bueno.

But, a simple way to do a chain adjustment is to measure the length of the bolts once you get chain slack set. Of the bolts are even on the ends and the chain is straight to the eye, tighten it down and double check. So long as the adjuster bolt thread count or length matches you're good.

[Jspooner]

I measure from the center of the swing arm pivot bolt to the center of the rear axle when I adjust my chain.

[forexer]

I've always adjusted the chain the same way STRIKER suggested however, I use a Vernier caliper to measure with and as long as each side is within .030 it's good to go

"A simple way to do a chain adjustment is to measure the length of the bolts once you get chain slack set. If the bolts are even on the ends and the chain is straight to the eye, tighten it down and double check. So long as the adjuster bolt thread count or length matches you're good"

measuring from the swing arm is also a good option however I found that I lose some accuracy trying to measure over that much distance - It's hard to keep the tape measure at the exact same angle on both sides.

What matters is - in the end is that both sides are even as possible

[forexer]

If you have an adjuster with a big hole where the small hole one should be how do you make sure the wheel alignment is correct because the marks on the adjuster and swing arm will be off?

I found out that the ones on this bike are aftermarket adjusters and therefore do NOT have "any marks on the adjuster" like the OEM ones have and whoever installed them installed 2 big hole adjusters instead of one small and one large.

to answer your question - you make sure the wheel alignment is correct by measuring both sides

[SoCal250]

I measure from the center of the swing arm pivot bolt to the center of the rear axle when I adjust my chain.

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