280 - Retarding The Spark

[cdn280]

Nobody is willing to share their repair cd so far, and I've read that retarding the ignition timing can help with the need to run 95 octane (to maybe just normal premium 91 octane) and also soften the power a bit for me. (first real trials bike) So that leads me to my question.... can someone tell me how to go about doing this and check where what its set to now? Maybe need a flywheel puller, i would imagine ?

btw - its a 2002TXTi

Edited November 14, 2005 by cdn280

[outlaw dave]

Maybe you should tell us where you are located? I assume by your av that you are in Canada someplace.

[cdn280]

Maybe you should tell us where you are located? I assume by your av that you are in Canada someplace.

<{POST_SNAPBACK}>

Central Ontario... Lindsay area. Is that going to help me ?

[gasgas]

maybe

But yes, retarding the timing will help when using lesser octane petrol, since lesser octane petrol burns faster then higher octanes you can help the egine with backing off the timing a tad.

What year is this 280, as with mine bike, (a pro 2002)i have to alter the position of the pickup coil which trickers the cdi.

[cdn280]

Hi George, yes mine is the PRO same year/model as yours. I did acquire a rebuild video but haven't watched it all yet. What do you need to do it? Flywheel puller? Dial guage?

Or, you can tell me to finish watching the video you lazy $@#, cause its in there.

Mike

[gasgas]

cdn, the pickup coil is easy accesable but to alter the timing you have to widen the bolt holes which keep it bolted to the case. To be able to work on it, you have to pull the flywheel with a extractor and loosen the stator and pickup coil from the engine.

[cdn280]

Thanks George, I'll take a look in there. Whats the best way to check it and whats its set too ?

[jtt]

The pickup is external to the flywheel on the Pro models. You can see it if you remove the ignition cover on the left side of the motor. The position is fixed (non-slotted mounting holes). As GasGas mentioned, you need to remove the pickup and carefully slot the holes to permit it to move slightly counterclockwise. There is little room to do this though, so the best you can hope for is a couple of degrees in most cases.

There is also a head gasket spacer available from the UK that will drop compression and take some of the bark out of it. This seems to be the most popular solution. You can also add basegaskets to accomplish the same thing. GasGas lists 3 different thicknesses of gasket for the Pros, you can mix, match and stack as you see fit. Raising it from the base gasket also has the effect of raising the port timing slightly, which will also soften the bottom end (and put it higher in the rpm range).

It also helps to fatten the pilot on these models, as it tends to make the power delivery less "sharp".

[cdn280]

Thanks JTT, good info. I like the bottom end just fine, so maybe the head gasket spacer is the way to go for me, after I try the slower black throttle tube first. What dealer to you recommend for parts in NS? I like the idea of ordering out of province to save some tax, plus I refuse to pay retail.

Can you point to a link for the spacer? Pllsss.

Edited November 18, 2005 by cdn280

[jtt]

Thanks JTT, good info.  I like the bottom end just fine, so maybe the head gasket spacer is the way to go for me, after I try the slower black throttle tube first.

If you drop compression, whether it be from the head spacer or the base gasket, you are going to loose a little bottom end...simply a matter of less compression. I think you'll probably find the slow throttle may be all you'll need and be happy with that. I've also found it useful to drop a tooth on the front sprocket, making 1st gear a little slower and more controllable.

What dealer to you recommend for parts in NS?  I like the idea of ordering out of province to save some tax, plus I refuse to pay retail. 

We're fortunate to have the Canadian importer right here in my home town. Here is the local dealership I use...RPM Cycle

[cdn280]

Coincidence?? I found RPM from a TrialsCanada page after this post. I ordered some stuff today from Barry before reading this.

Thanks

Mike