Commando chain tension

Good question Hans, I think I've only needed to adjust theRenold chain on my Commando twice in the last 22 years, since fitting this chain, about 6,000 miles since then on it. (I know)

I actually adjust all my chains using the same principle where a centre stand is fitted and make the initial adjustment on the centre stand. This way I can check the alignment by sight and sound by spinning the wheel.

I check the tension after adjustment in the usual way, looking for about an inch of upward movement at the centre between the sprockets.. Then turn the wheel, constantly checking the tension. If a tight spot occurs then the chain needs to be adjusted at that point to give a small amount of play, up to half an inch but no more. (All of this assumes that the chain is still serviceable.)

I check the tension then on the side stand and keep moving the bike along until I'm satisfied the play is acceptable along the whole length. I don't think there is a set formula.

A well adjusted and lubricated chain on good sprockets means long intervals between adjustments. (Riding style accepted of course)

How about doing it once on its wheels with a helper sitting on it then putting it on the centre stand and measuring the amount of play in that format? (and, of course, posting the resultant data on here!)

It is best to check the free play with somebody else sitting on the bike but this is not always possible. So on my 1972 750 Commando I worked out that on its main stand about 25 -30mm of up/down was about correct.

While talking about chains I have just had to replace my rear chain for the second time in 5 years. The last one (Renolds) has only lasted 8000 miles despite a regular spraying with grease and dunking twice a year in a Linklife pot. The problem with this last chain is side play. It has not stretched much but was beginning to rattle badly against the chain guard and gearbox.

I am not too impressed by these Renolds chains....whoever makes them. The primary chain on my Dommie (also a Renolds) began to show lots of side play as well after only 300 miles. See attachment.

The JWIS brand appears to be better but heavier.It also uses strange connecting link pins. The Regina make seems to rust quickly. Has anyone got better suggestions for good Norton chains?

I'm surprised there was no tight spot to compromise with or excessive slack spot.

How about getting a ratchet strop over the back of the frame and hooked onto the swinging arm on both sides, then crank the strop down until it's in the same position as with your weight on. Then adjust the chain, seemples.

Previously david_evans wrote:

How about getting a ratchet strop over the back of the frame and hooked onto the swinging arm on both sides, then crank the strop down until it's in the same position as with your weight on. Then adjust the chain, seemples.

I know this is resurecting a very old thread but I have been struggling (without an assistant) to check where the tightest point of the chain is.

Using Dave's idea of a ratchet strap, If you measure from the ground to the centre of the wheel spindle and then compress the suspension such that the centre of the clutch inspection cover is the same height above ground. then the distance between the two sprockets will be at the maximum.

This is the point where you should be adjusting your chain.

Theoretical at the moment, does it make sense ?

If you want data, I'd have thought the principle would be to have the clutch centre, swinging arm pivot and rear wheel spindle in a straight line ...? It may in fact be the case, but without looking at my bike or a plan it doesn't seem obvious to me that that would be guaranteed by only checking that the clutch centre and wheel spindle were the same height off the ground. I use about 1?" slack on the centre stand, not based on any data, just experience â adjusted at any tight spot, certainly, and then re-checked after tightening the spindle. If the chain's too tight you can feel it in the ride, and you'd better do something about it pdq!

just get a buddy to ride along beside you and se what is going on with the chain over an undulating road. ( don't crash)