Check your chain tension!

[Qwerty1234]

Hi everyone

I've had a sneaking suspicion that the chain tension on these chinese bikes was a bit iffy, it looked quite loose yet quite tight when sitting on the bike. There's no official figure I could find for my Dpro 160 and scouring this forum I found the general consensus to be "about 2-3 fingers". This didn't sit well with me so I decided to check it properly. Here's a little video showing the problem

[YOUTUBE]NkbgWh6wPbU[/YOUTUBE]

I'm gonna leave it for tonight but the point of the video is to show you just how tight chains can get, there's quite a lot of tension at the middle of the stroke and it would certainly wear the chain and sprockets, and likely cause some minor gearbox issues, especially under full throttle on landing. It'll also affect the rear shock action to a small degree

The idea is to set the tension so the chain is about as tight as it can go at its TIGHTEST point, yet still allow a smooth linear motion. Once that is set, tighten everything down, check it again, double check it. Then reinstall the shock and set it on its side stand. Now you can measure the amount of tension you have and record that figure. When checking/adjusting in future, that is the tightest you ever want to go

Hope this helps!
Cheers

 

[my67xr]

i adjust mine to have 30 to 40mm up and down movement with my full weight on it.

the longest point that the chain runs is a straight line drawn from the centre of the front sprocket
centre of the swingarm pivot bolt, and the centre of the rear axle
so as long as your chain isn't too tight when the rear suspension is compressed to that it will be fine.

 

[Cordogs]

Timeeh had a good write up on it in another thread. If you could spare the 2 hours to read it, made all other the ways look dodgy.

I prefer the "that's close enough" approach!

 

[Qwerty1234]

I prefer the "that's close enough" approach!

You're mad!
Look at the video, whats happening under compression of the suspension is its pulling 'tightly' on the front sprocket. What do you think thats going to do over time?

 

[Cordogs]

You're mad!
Look at the video, whats happening under compression of the suspension is its pulling 'tightly' on the front sprocket. What do you think thats going to do over time?

Yep, I didn't need to watch that to work that out
However!

This is the Link I was talking about. Happy reading!
http://www.dualies.com/downloads/files/How To - Chain Adjustment.pdf