Stock rear shock stroke

[robo]

Can anyone tell me what the stroke on the stock XS650 rear shock is? I am replacing the rear shocks with something in the 13 1/2" range and would like to get a bit more rear travel if I can. I did search the forums and did not come up with anything.

 

[5twins]

According to the '78 shop manual, it is 80mm (3.15"). I don't know if that applies to all models.

 

[robo]

Cool, thanks! Do you know, is that the rear wheel travel or the shock stroke?

 

[5twins]

That's the shock stroke or travel. Slightly longer than stock shocks may not be much different in travel, only longer in length.

 

[robo]

Checked that manual myself- doeesn't seem to specify models (my frame is a Special, 1980). Hmmm....

 

[arcticXS]

Just make sure that there is sufficient clearance between the tyre and the fender etc. when the shocks are fully compressed. I got a pair of Ohlins emulsion shocks for a Triumph (Bonnie or Thruxton) that have 100 mm stroke, and are around 20 mm longer than stock, so they are fine. I don't think Ikon or Hagon offers units with 100 mm stroke, but Falcon (falconshocks.co.uk) may be able to custom build shocks to your specs. And maybe Racetech can as well.

On my 1977 XS 650 D, the rear wheel travel is around 120% of the shock stroke, so a 80 mm stroke gives 96 mm wheel travel, and 100 mm stroke gives 120 mm wheel travel. Specials and older models may differ, due to shock angle and mounting point locations. Just take some measurements and do the math.

 

[robo]

Good info. I am looking at a 13.25"/336mm Ohlins shock with 98mm of travel. I have modified the subframe- I cut off the rear hoop just behind the shock mounts and am welding in a new hoop that will angle up slightly from the weld. So the seat pan will be flat to the just aft of the shock mounts and then angle up at say 10 degrees for the last 7 inches. I am planning on running a 120-100 x 18 tire on an 18" tx750 rear wheel. No fender.

In a nutshell, I am mounting a shock that is something like 16mm longer than stock and adding 18mm of shock travel- so I am assuming that essentially evens out and the clearance should be adequate. Honestly I am not sure how I can guarantee the clearances until I have everything on the bike- but open to suggestions!