Quick Chain Tension Question

79 CR 250....i looked through the forum and found this but need some clarification...the H style tensioner is set from the top of the roller to the bottom of the swing arm...Is it set with the bike on the stand, on the ground or with the axle, swing arm pivot and counter shaft all on the same plane?
Mine is not an H style roller so I'm guessing i should measure from the top of the chain to the bottom of the swing arm?
thanks
bob

Squash the suspension down until the sprocket pivot and axle are in a line. Make the chain tight, make it less tight depending on how much mud/sand you expect. That is how I do it. That is for no up tight device like in the picture. Looks like the top of the chain in the diagram. I would think that 15-20mm would be a minimum. I do not think they had x ring chains like now back then and it might be touching by the end of the day? Before I took it off or the one bike I have that still has it I do that with the spring forced out of the way as I described above. Might try that and see what measurement that gets you on the stand. One is supposed to rotate the wheel to see if things change like a sprocket being out of round. Not that I ever found any noticeable deviation.

I looked in an 1983 manual, does not say an answer directly to your question just not to exceed 20mm. Kind of screwy in my opinion quite a bit of difference in rear sprocket sizes.

As Fran...k said. Drop the bottom mounts from the shocks, lift the rear wheel until the chain is at it's tightest. Adjust as required. Re-fit the shocks. Then take a measurement somewhere so you can do this in the future without the shock off hassle. I usually cut a small piece of timber to fit in a certain point as a gauge. Then mark it up as such and put it in your tool box.

That 20mm gap grows as the suspension compresses. Do you use the orginal chain tentioner roller?

no Bill it's no the original...i understand that it will increase under compression...that is why i asked what position the swing arm should be in when setting the adjustment..bottomed out or in line with the countershaft...from the replies it appears it should be set 15-20mm with the swing arm in line with the counter shaft....is that the way you set yours?

Bike on the ground....Vélo sur le terrain
Merci Claude!
Bob

That’s right when the suspension moves up the roller moves down. My 84/250wr is set this way.