Front and Rear Sprocket Torque Values

[bcware]

I am having difficulty finding the torque values for the front sprocket nut and rear sprocket nuts. I've checked the Haynes a few times and searched on here; I must be missing it somehow.

1978 2e by the way.

 

[Scorpio1963]

BC have you tried google?

 

[bcware]

Yes, nothing yet. The search terms, unfortunately, yield a lot of irrelevant results. Throw "sprocket" and "torque" in there and you get many people just discussing how much torque the engine makes with different sprockets.

 

[drewpy]

rear drive sprocket 29 - 36 ft lbs

front sprocket nut 36 - 58ft lb

 

[bcware]

Thank you!

 

[Scorpio1963]

Thanks to Drewpy you got your answer.
As far as google I can usualy find my answers im looking for there but not always.Sometimes I use DogPile or other search engines.

 

[jeffrollins]

rear drive sprocket 29 - 36 ft lbs

front sprocket nut 36 - 58ft lb

Hello, I am fixing up a 1980 xs400SG for my son. When I pulled the rear wheel off, the sprocket mounting nuts were less than finger tight, and one of them was missing. Would the values for the rear sprocket nuts be the same on my bike as you quoted BCWARE for his?
P.S. This is my first post to this site. Hope I am doing it right.

 

[Scorpio1963]

Welcome Jeff

 

[bcware]

1980 xs400SG

Would the values for the rear sprocket nuts be the same on my bike as you quoted BCWARE for his?

If your bike is also an SOHC I would bet good money that the torque values are the same!

 

[jeffrollins]

If your bike is also an SOHC I would bet good money that the torque values are the same!

Thanks BCWARE. It was pretty nerve racking when I realized I had rode this bike 20 miles home after I picked it up. The bend tabs to lock them were flared out as if someone had worked on it and not finished the job. You can bet I will lock the nuts after the torque.

 

[Winnipeg_79_XS400]

rear drive sprocket 29 - 36 ft lbs

front sprocket nut 36 - 58ft lb

First Post here, I read above the torque values for the front/rear drive sprockets.

I read in the manual (p.5-43) front is 7.2 Ft. lbs

Any tips on cracking the bolt for the front? I have read a number of ideas on how to stop the sprocket from spinning (some seem outlandish)

Chris 79' XS400

 

[xschris]

My yamaha manual states 47 lbs for the front one. 7 lbs is very light, kind of like hand tight. I remove mine by putting the rear wheel down on the ground and turning the nut with a socket wrench. I set the rear one to about 30 lbs.

 

[drewpy]

its could be the bolt system with two bolts instead of a nut?
the sprocket has a sort of cover which turns and locks on the sprocket and the sprocket can float. Honda used these a lot. Have you a DOHC? and not seen these on SOHC's
if its only 7 lbs ft surly you can take it off with a sharp tap with a hammer?

 

[Winnipeg_79_XS400]

ill go with 47, tracking the rear axel/bike down hand tight the codder pin. What about the 4 bolts holding the sprocket to the rim?

 

[Winnipeg_79_XS400]

Just so i reading the manual rite lol,

 

[xschris]

I use 30 for the rear. That manual looks like it's for a dohc seca model. Those used that type rear wheel. If you have a sohc xs400 don't use that manual. Post a pic of your bike.

 

[Winnipeg_79_XS400]

Looks like I used the wrong manuals (found on here). It's 1979 xs400 f Sohc, I believe lol

 

[xschris]

Yep sohc xs400, looks to have a few mods to it but sprocket torques will work.

 

[Winnipeg_79_XS400]

Thanks again for the help Chris!

The bike is new to me (3rd owner). I put the bars and mirrors on, rest came with the bike!

 

[xschris]

Those mufflers are also not stock. Make sure the bike is jetted/tuned for them. Plug color will give a good idea.