Zong Sierrra: Silly Rabbit, Bike chains are for kids?
 

I have adjusted this chain probably 5 times at least in the last 1000 miles, but keeps jumping back to the old setting? What am i doing wrong?

Heres the scenario: For example, If you look at the chain tensioner doohickey it looks almost like a 3/4 of a clock... with groove positions at 1oclock, 2oclock, 3oclock, 4oclock, 5oclock, 6oclock, 7oclcok, 8oclock, 9oclock and so on.

When I first got the bike, the tensioner pin was sitting in the 5oclock position, and after some riding the chain loosened up quite a bit. So i adjusted it to the 6oclock position which tightened the chain up some but still allowed some play in the chain.

I tighten everything up, TIGHT! and i send my son on his merry way. A week later, i check the bike and both tensioners are back at the 5oclock position again! How is this happening? Currently I am using a 1/2" breaker bar (both sides) on the thing and it is TIGHT when it leaves me.

Am i doing something wrong?

how do i keep the chain tension to the proper amount?

Is it getting jumped?

Maybe there's a clue in the chain tension. How are you determining what the correct tension should be?

No, the bike is electric started only.

I am roughly gauging the tension. I am leaving it with about 1/2 inch play upward or downward while my son is sitting on the bike.

When its in the 5oclock position (the position it seems to jump back to)there is about 1 to1 1/2 inch play in the chain in either direction, and to me it seems to be too much.

Does your bike have a spring loaded chain tensioner?

not sure since i didnt get a manual... but its a zongshen sierra

No, the Zong does not have a spring-loaded chain tensioner.

DW, are you saying that the chain snail adjusters are returning to a previous, lower setting? That shouldn't happen unless someone is loosening the rear axle bolt.

AZ is asking you if your son is jumping the Zong off small hills, and landing with a substantial impact. This behavior might stretch the chain enough to pull the snail adjusters back to a lower setting.

Spud :)

Spud,

Yes. I adjust them to one position and later it returns to the previous position.

OH! 8O. As far as i know he hasn't been jumping the bike, its primarily a commuter bike. But he is 19 years old and he has been on the trails with me. I wouldn't put it past him if he has jumped it recently. I will ask him tonight.

Is there any limit to how tight the axle bolts can be? I mean i kind of worry i might make it too tight. (which might be part of the problem)

Dave

I don't know what's causing the problem but I don't see how jumping or otherwise beating up the bike would do it.

1/2 inch slack would be way too tight on my HSUN, so maybe it's the same on a Zong. Try adjusting it with your son on the bike and the suspension compressed. You may also have a lubricant on the axle bolt that allows it to move.

Personally in 30 years or riding and wrenching that's a new one on me.

I agree. It is far better to adjust the drive chain a little too loose, than a little too tight. ;) While your son is sitting on the bike, with the suspension compressed, the Zong drive should have about 1-inch, to 1.5-inches of slack.
I tighten my axle nuts very tight. I am more concerned about the axle nut coming loose, than overtightening it. On page 6, Table 2-8, my Zongshen Sierra 200 Motorcycle Maintenance Manual says to tighten the rear axle nut with a torque of 70-90 Nm. These metric values equal a range of 52-66 Lb-Ft.

http://www.boltscience.com/pages/convert.htm

I would guess you need to tighten the rear axle nut harder, DW. ;)

Spud :)

??? The Zongshen sierra has both options, electric start and kick start.


When you loosen it to adjust it, after you get it where you want it, do you push forward on the wheel before tightening the bolt to get all the slack out? (meaning no space between the stud on the swing arm and the adjuster plate) Also, every time I adjust mine, I put a small dab of loc-tight on the bolt just for peace of mind.

That's a very important thing to point out, DR. :) You should push forward on the rear wheel to "seat" the snail adjusters tightly against the studs on the swingarm, then tighten the axle nut sufficiently before your son mounts the bike. Then check the chain slack. If the chain is adjusted properly, have your son dismount the motorcycle. Then recheck to see that the snail adjusters are still tightly seated against the studs on the swingarm. Of course, both snail adjusters should be placed on the same setting number. If the snail adjusters are still correct, tighten the rear axle, and lock everything in place. :)

Spud :)

:lol: that's what I meant to say :lol: , glad someone understood what I was trying to spit out. Kind of hard to write exactly what you mean sometimes on the computer :roll: :lol:

Good point. I whack the rear tire forward with my fist or a rubber mallet.

Don't whack it off the stand, however... :roll:

Yep, I have knocked the tire forward and backward from the pin to unseat and seat it.

I will try to locktite the bolt, and also will use a torque wrench to tighten the bolt to see if i have any better results..

thanks for the help!
Dave