[scotty97]

I'v just purchased a 1999 txt270 and the front end feels nice but could do with a bit more REBOUND, please could someone explain how to tweek the adjusters on top of the shock before i look and changing fork oil etc... or would it be worth changing it anyway as i dont know when it was last changed, or if it ever has been??

[JSE]

scotty97, on Jul 13 2009, 01:11 AM, said:

I'v just purchased a 1999 txt270 and the front end feels nice but could do with a bit more REBOUND, please could someone explain how to tweek the adjusters on top of the shock before i look and changing fork oil etc... or would it be worth changing it anyway as i dont know when it was last changed, or if it ever has been??

The knobs at the top of the forks are essentially "high speed" tuning adjusters, not MPH of the bike, but the velocity of the shaft moving inside the internal damping cartridges, so you may not realize a big change. You can start by adding a little penetrating oil under the knob to loosen them up (they are often slightly corroded and difficult to turn in older forks) and slowly and carefully turning the knobs back and forth. The 99' forks seems to work for most riders with the compression knob (black on left) turned fully out and the rebound knob (red on the right) fully in (lightly bottomed, as in all suspension adjustments). You can change the fork oil in the right leg to 315-320cc's of 2.5 weight, which will decrease the rebound a lot.

What is more than likely actually happening is that the forks are binding, which is usually more apparent in the rebound phase. Try loosening the fork and axle clamps (and remove the fork brace) except for the top two capscrews on the tripleclamp and move the forks up and down to "center" them, then tighten the lower tripleclamp to 18 ft lbs, center the forks again and tighten the axle clamp (about 7-9 ft lbs). The fork brace always goes on last. The screws should drop in the holes and thread easily, if not, use a file to enlarge the holes, don't force them in.

If it's a used bike, the upper tubes may have been bent slightly, which will also cause binding, and you may want to check that out.

Cheers.
Jon

[scotty97]

Ok cheers i'l check them out, just to check you said by adding that oil it would DECREASE the rebound, but i could do with a bit MORE rebound. I think looking at them last nite they have got a slight bend. perhaps i'l strip them down after all?????

[JSE]

scotty97, on Jul 14 2009, 04:37 AM, said:

Ok cheers i'l check them out, just to check you said by adding that oil it would DECREASE the rebound, but i could do with a bit MORE rebound. I think looking at them last nite they have got a slight bend. perhaps i'l strip them down after all?????

Doh!
I misread the request, gotta take some time after a week on the road before reading posts.
Change the specs on the rebound side fork (right side) to 7.5 weight and 290cc's of oil. If the fork oil is black to a degree, that's the outside of the springs that have scraped off (it's normal). Be sure to clean out the bottom of the lower tube where the gunge collects. Sometimes there is enough scraped spring residue in the bottom of the leg to interfere with damping (it collects in the "shim stack" of the cartridge where the actual damping proceedure is done).

Jon

[scotty97]

If i want to wind the black/red adjusters fully in. Is that clockwise or anti-clockwise???? sounds a silly question but i cant see the + and - marks on my forks

[andy198712]

clock wise is more, anti is less, like a screw thread

[scotty97]

Had the forks rebuilt in my local trials bike shop, got to say it feels like a totally different bike, just got a few slight tweeks to make and lampkin can look out!!! ha ha i wish. thanks for your advice

[JanDyb]

scotty97, on Aug 20 2009, 08:08 AM, said:

Had the forks rebuilt in my local trials bike shop, got to say it feels like a totally different bike, just got a few slight tweeks to make and lampkin can look out!!! ha ha i wish. thanks for your advice

What tweeks (tweaks?) did they do? Curious..

-Jan

[scotty97]

They just changed oil, seals etc and put in a nylon spacer cos the springs might not be as strong as the were new. the shop said i'd have to tweek the adjusters to set rebound etc to my own preferences, but they seem quite good as they are, but im only a beginner to trials so would i be able to tell??????