Chain Adjustment...

[Rollins]

I took my RS125 to my dealer today to get the chain adjusted, as I have neither the equipment or the know-how to do it myself at home (I should enrol on a Bike Maintenance course really).

I got it back home to clean & lube the chain, and noticed it seemed rather tighter than before (no surprises there). But there is no free movement on the chain at all, the only movement feels like I'm stretching the chain.

My manual and various web sources all say that 25mm of sag is the ideal tension, but is that 25mm in the free up & down movement of the chain when only lightly pushing it until it tenses up, or when you really press up & down on it & it physically cannot move any more?

Also, my rear wheel doesn't spin very freely up on the stand, and when I'm slowing down, I can hear the chain make a kind of grinding noise. Is that normal?

Any words of wisdom are much appreciated.

[kev]

Your chain may be worn out and you might have tight spots in it which will meen the chain needs changing.

If the chain is tight and it is making grinding noises and making the wheel hard to turn it is not advisable to ride the bike as it can knock out the rear wheel bearing or even the final drive bearing which you really don't want to go changing.
____________________
20:02:36 Jammy-R6: any holes a goal
20:02:48 kev: even if its a hairy mans arse
20:02:56 Jammy-R6: hell yes

[Rollins]

Cheers for that kev, but sounds odd because I bought it brand new this year in January, and I've only done 3000 km on it. I clean & lube the chain about once every 2-3 weeks, riding it nearly every day, except when it's pouring down

Could the dealer have cocked it up by setting the maximum tension and then forgetting to actually give some sag before tightening everything back up??

[kev]

They may have just done it too tight.
____________________
20:02:36 Jammy-R6: any holes a goal
20:02:48 kev: even if its a hairy mans arse
20:02:56 Jammy-R6: hell yes

[leg-end]

A couple of points on checking chain tension.

1. As you spin the wheel you'll notice that at some points the chain will be slacker than at other points, this is normal. The chain tension should always be checked at the tightest point.

2. The tension "measurement" is the maximum deflection up and down.

3. The tension should be checked when the weight of the bike is on the rear wheel, as the suspension compresses it will put more tension of the chain. In fact if you ride often with a pillion it is best to have your chain adjusted at the slack end of the range.

4. Always check the wheel alignment using a straight line with the front wheel (such as a nice straight plank or taught string) since the adjustment marks on the swing arm are often inaccurate.

It's worth buying the Haynes Motorcycle Workshop Practice Techbook as it explains all the basics of maintenance.

[Rollins]

Fantastic leg-end, cheers. I bought myself the Haynes Motorcycle Maintenance Techbook, as well as a paddock stand and a torque wrench, hopefully I can have a go myself as I don't trust my dealer mas much as I used to.

[leg-end]