Friction Zone

[Foom]

Hi,

I am new to everything: the forum, the Ninja, and riding. I finished the MSF BRC last week and picked up a 2003 EX250 with ~4800 miles. The bike seems to be in good condition with one exception, the friction zone is really, really small. Let's say the clutch lever has a 6" swing, I would say the clutch engages and disengages in the last 1/2". I've read as much as I can find online, and I can't find anything that says "adjust this to change the friction zone size" (not location, I get that part).

Thanks
Foom

[Alex]

It sounds like it is behaving normally. The friction zone isn't particularly large on most bikes, and it's definitely not on ninjettes. As you may have found already, there are adjustments to the cable you can make to move it around it a little, but make sure that you don't tighten it so much that there is no free-play.

[alex.s]

+1 on being normal. the only bikes i've ridden with large friction zones were msf bikes.

it is possible to change though. you can do it by modifying the lever (or buying one that's been modified) so the distance the cable is pulled in relation to how much you pull the lever is changed...

as in if you relocate where the cable attaches to the lever so that it's radius of rotation around the lever axis is greater, the amount the lever pulls on that cable will be increased (decreasing the 'size' of the friction zone) the same is true of the opposite... bring the cable mount point in closer to the lever rotation axis and you now have a 'larger' friction zone.

i've never seen levers built by a company for this purpose though... though making your own levers wouldn't be terribly hard...

[Foom]

The bike I had in the MSF was a Suzuki GZ250 and the friction zone seemed like half of the lever---so my bike was a bit of a surprise. I thought maybe the clutch springs were shot. If it's normal, I'll get used to it. Thanks

[Alex]

It's likely the other way around. The clutches on most of the MSF bikes are torn up to all heck, so their area of slipping (friction zone) may get wider and wider over time. Even when fully released, the amount of force that can be absorbed through their clutches is likely pretty low due to the wear and tear. The good news is that they use such low powered scoots, that the clutches can be almost gone and they still work well enough to get folks through the class.