18 replies to this topic

[TrialTrial]

Hi Guys, I got a few woes with my tired txt 2000 280.

(1) Very bad clutch drag. I know it could be anything from master cylinder, to the clutch line, to swollen discs - Suggestions on the easiest diagnosis?

(2) BRAND NEW Electric fan is intermittent. It started to overheat, and fan wasn't working, so I jumpered the thermostat in the field - still didn't work. Road the bike a bit, then it started to work. Drove more and it didn't. I guess its either the alternator, regulator, rectifier or the NEW FAN is busted. Suggestions on how to diagnose?

(3) The kick starter does not return. I have to return it by hand, and it is a bit of a struggle to return it back to position (i.e. VERY sticky). How do I determine what part is bent?


thanks for all the help.

[lineaway]

Did you just buy the bike or have you had it awhile? Did all these just happen or after it`s been apart. A little history goes a long way.

[TrialTrial]

I got the bike this way.

[JSE]

(1) Very bad clutch drag. I know it could be anything from master cylinder, to the clutch line, to swollen discs - Suggestions on the easiest diagnosis?

Make sure the M/C piston is returning back fully to the circlip, this may require backing off the adjustment screw on the lever. When pulling the lever in, you should get pressure soon into the stroke, otherwise the piston seal may be worn and need replacement or there may be air in the line. I'd also take the sidecover off (when you check the kickstart shaft) and check the clutch itself by taking it apart.

(2) BRAND NEW Electric fan is intermittent. It started to overheat, and fan wasn't working, so I jumpered the thermostat in the field - still didn't work. Road the bike a bit, then it started to work. Drove more and it didn't. I guess its either the alternator, regulator, rectifier or the NEW FAN is busted. Suggestions on how to diagnose?

If the fan runs on a 12V source, it's probably o.k. The fan module is probably the next suspect in line followed by the voltage regulator, thermoswitch and then the stator output. All components should be checked after making sure there are no worn wires, loose connections, corrosion etc. in the electrical system, of course. Intermittent operation of the fan is normal, otherwise you would not need the thermoswitch.

(3) The kick starter does not return. I have to return it by hand, and it is a bit of a struggle to return it back to position (i.e. VERY sticky). How do I determine what part is bent?

You will need to take the sidecover off and look. Check the spring for distortion and try to figure out where the assembly is binding, in the sidecover or where the shaft goes into the case.

Jon

[TrialTrial]

Awesome Jon, thanks for the info - I will dig into it right away, and post my findings.

Don

[TrialTrial]

OK, well tore the bike down. Here are the findings:

Clutch
- lever returns nicely to the circlip, then there is some freeplay with the levler (looks good to me)
- pulled off the clucth cover and put a dial guage on the clutch stack
- as soon as the lever engages the clutch pack starts to move (good thing)
- the maximum movement of the clutch pack is .035" (0.89mm)
- pulled the clutch pack apart and measured the friction plates they are all about 0.013" (0.33mm) thick

- found one issue: the nut holding the basket on was not tight, I was able to turn it off with minimal torque. There was no locking tab either, although I am not sure how one can fit inside.

- any idea what the clutch specs are for this bike?


Kickstarter
- the shaft is loose in the casing, but quite snug in the cover
- the cover bore seems OK
- I cannot tell if the spring is distorted - not sure what to look for here
- when I try to put the case together with the shaft, it is binding somewhat
- I put the kick start shaft between to centres (on a lathe) and measured runout on the to bearing surfaces - .001" tops

[JSE]

OK, well tore the bike down. Here are the findings:

Clutch
- lever returns nicely to the circlip, then there is some freeplay with the levler (looks good to me)
- pulled off the clucth cover and put a dial guage on the clutch stack
- as soon as the lever engages the clutch pack starts to move (good thing)
- the maximum movement of the clutch pack is .035" (0.89mm)
- pulled the clutch pack apart and measured the friction plates they are all about 0.013" (0.33mm) thick

***Those spec.'s do not seem too bad. You might want to line the springs up on a flat surface to see if any have sacked out, which would cause drag.

- found one issue: the nut holding the basket on was not tight, I was able to turn it off with minimal torque. There was no locking tab either, although I am not sure how one can fit inside.

***I think only the 125/200 models of that year use a locking tab.

- any idea what the clutch specs are for this bike?

***I don't have a plate to measure but the fact they all measure the same amount indicates they are probably good.


Kickstarter
- the shaft is loose in the casing, but quite snug in the cover
- the cover bore seems OK
- I cannot tell if the spring is distorted - not sure what to look for here
- when I try to put the case together with the shaft, it is binding somewhat
- I put the kick start shaft between to centres (on a lathe) and measured runout on the to bearing surfaces - .001" tops

***I don't think the 2000 uses a bearing on the case side of the kickstart shaft, just a machined recess. The spring spacer may be binding the spring operation or holding the shaft out somewhat. For a 2000 TXT parts list try http://www.trialspar...a.com/tech.html and you can download the manual to see what the spring should look like.

Jon

[TrialTrial]

Well I figured out the kickstarter problem. There is an aluminum collar that is press fitted onto the shaft. On the collar there is an indent for the kick start spring. This was not aligned with the kick start spring hole, so it rode up higher on the shaft, causing the whole assembly to be crushed together when the case was bolted down.

OK one down, two to go...

[lineaway]

Clutch needs to be assembled correctly, If I rememeber the TXT had a mark on the hub and one on the pressure plate. Any other tips Jon?

[TrialTrial]

OK, now into the clutch - Jon you said that the 280 did not have a locking tab - the parts book agrees. Any clue what to torque the nut? 40ft-lbs? What about a little bit of (very carefully applied) red locktite? I am surprised they dont have a locking tab.

Anyways the clutch springs all measure the same height +/- 0.1mm

[JSE]

lineaway, on 13 September 2011 - 12:50 AM, said:

Clutch needs to be assembled correctly, If I rememeber the TXT had a mark on the hub and one on the pressure plate. Any other tips Jon?

There is a line (like lightly hit with a chisel) on one of the spring towers and a mark by one of the spring tower holes on the pressure plate that need to be aligned.

Jon

[JSE]

TrialTrial, on 13 September 2011 - 01:01 AM, said:

OK, now into the clutch - Jon you said that the 280 did not have a locking tab - the parts book agrees. Any clue what to torque the nut? 40ft-lbs? What about a little bit of (very carefully applied) red locktite? I am surprised they dont have a locking tab.

Anyways the clutch springs all measure the same height +/- 0.1mm

I'm trying to remember, but I think the hub nut has a very fine thread pitch and you may want to go a little less so as to not strip the threads, maybe 25 ft lbs? The locking "pressure" is carried over a larger area with the fine pitch. Red Loctite would be a good idea just to be safe.

Jon

[TrialTrial]

OK, I cleaned up all the parts - the clucth plates all are flat, athough do show *slight* discoloration/scoring. I cannot feel anything though. I figure I can clean these up with some 2000 wet/dry on a surface plate.

Here are some pictures of the clutch hub and basket. Definitely some wear and a ding or two.

On the hub I can clean up the dings and the burrs, but not sure how (or even if) I should clean up the wear marks.

On the basket, there are some burrs on the edges that can be cleaned up, what about the wear, should I bother?

thanks for all your help Jon.

Edited by TrialTrial, 13 September 2011 - 04:25 PM.

[JSE]

TrialTrial, on 13 September 2011 - 03:58 PM, said:

OK, I cleaned up all the parts - the clucth plates all are flat, athough do show *slight* discoloration/scoring. I cannot feel anything though. I figure I can clean these up with some 2000 wet/dry on a surface plate.

Here are some pictures of the clutch hub and basket. Definitely some wear and a ding or two.

On the hub I can clean up the dings and the burrs, but not sure how (or even if) I should clean up the wear marks.

On the basket, there are some burrs on the edges that can be cleaned up, what about the wear, should I bother?

thanks for all your help Jon.

Actually, that doesn't look too bad to me. Some riders use a file to straighten the sides of the fingers but that may cause a little more "slop" in the drivetrain. I polish the sides of the fingers and the slots on the hub (all the friction points the plates make contact with) with a rubberized abrasive called "Cratex" and I think it helps the plates move easier and results in smoother clutch operation.

Jon

[TrialTrial]

Thanks for the tip. I polished up the hub and the basket (buffer wheel) and put it all back together. It all wwent back togtehr very well. Kick starter works great. Hopefully I can test the clutch tomorrow.

However, the plot continues...

I went to rebuild the clutch master cylinder, pulled it apart, then opened up the new parts. Hmmm - its quite different. Was there a parts update to the clucth m.c.? The piston is different, although the same diameter. The spring length are different, although when combined with the piston, the overall lengths are close. And the new rubber end seal is way too large.


Suggestions? Use it as is?