Front tire on the rear? That's how it came to me.

[JimF]

It's been fun being able to ride my "newest" 250 and to be able to depend on it. I am in that stage where all the major sorting is done and now with some miles under my belt I have begun to notice the minutia that's left with this bike and to be able to think about resolving it.

Today was my first ride in rain, and twice under heavy braking on wet pavement the rear end broke loose. That is to say the rear tire lost all adhesion and the back end starting moving sideways. I don't recall ever having this problem with the Mach 1. I recall locking the rear tire on the M1 (albeit on dry pavement) and it stayed straight as an arrow.

Courtesy of the previous owner, this bike has a front tire mounted on the rear rim.

250_back_tire.jpg

My knee-jerk reaction is to point the finger of blame on the front tire treads as not serving me well on the rear, but I would welcome corroborating or differing opinions.

Thanks

Jim

[DewCatTea-Bob]

" and twice under heavy braking on wet pavement the rear end broke loose. That is to say the rear tire lost all adhesion and the back end starting moving sideways. "

____ It seems to stand to reason that if the rear locks-up while the front is also braking , that the rear/back-end of the bike would then become inclined to try to come-around & surpass the front-end, since the front-braking is able to slow the whole bike down more-so than the rear-braking can. _ So during such "heavy" braking, it would be fairly odd if the back-end did NOT become inclined to slide-out (from being otherwise in-line with the front).
However when not riding with any turn at all, and thus the bike is going completely upright & straight,, if the front-brake is not also in use, then locking-up the rear-wheel should not cause the back-end to slide-out.


" this bike has a front tire mounted on the rear rim.
My knee-jerk reaction is to point the finger of blame on the front tire treads as not serving me well on the rear, "

____ I've only ever encountered that done just once before, but I didn't leave it that way and-so have no real experience with it not working well,, however I-myself tend to doubt that the tire-type is inclined to become the possible cause your rear slide-out issue.
__ If you could note the exact specific conditions under which your issue continues, and could also swap the rear-wheels of your two DUKEs when doing such testing,, that ought certainly help solve where any fault might reside.


Hopeful-Cheers,
-Bob