Hybrid Revisited

[Genesis]

your bike makes me mad at my self for not getting mine done, it looks sweet

[DonTZ125]

Mr Freeze - you are courting a serious high-side, and you need to figure this out fast. First simple check - is your rear tire overinflated? Many places pump up a new tire to 60+ psig as part of mounting / beading it; not all of them bleed it back down to running pressure. Is there mold release / oil / coolant on your tires? Did your g/f try to be nice and clean your bike, including a good Armor-All of your tire tread? (seen it...)

Second - is your chassis set up correctly? You may have too much weight on the front, not enough on the back.

Technique - Are you cracking the throttle BEFORE you tip in? Where are you carrying your weight - on the seat, tank, bars, pegs? If you feel your rear start to get loose, put some weight on the OUTBOARD footpeg; this will transfer weight back to the rear tire.

Good luck!

[mrfreeze5]

Tire pressure is good. I check it weekly. They have about 1000 miles on them since new. I did not have this issue until I changed out my main jet. It really created more power than I expected and after that is when this started happening. The first time could have possibly been due to chassis setup since the rear shock was set a bit soft on the preload. I adjusted this and everything is pretty happy on the chassis now. It did it again a few times which may have been attributed to wet tires, but I dont think so.

One thing that might be causing the issue is my body position. My tank is moved forward a little, the clipons are down, and the rearsets are down, and I suspect my whole weight is shifted forward slightly as a result. My bike likes to keep me in a position where my chest is close to the tank. It feels like most of my weight is carried in my crotch(hehehe), basically where the tank meets the seat.

The I am thinking I am not throttling too early, but Im no pro. Its always after I am tipped in and exiting the turn. It only does it on a pretty good lean, and road conditions could be to blame, but it has done it every time I have gone out riding over the last few weeks despite conditions. There really isnt enough reaction time to weight the outside peg when it happens. Like I said before, its just a brief shimmy in the bike. It almost feels like the rear shock unloading, but Im pretty sure its not given the circumstances. It might have been the first time, but not the others. It always happens as i apply throttle though. I may just be getting on it too hard, Im not sure. I havent had a lot of time on the road either since the rejet and the new power is tempting to play with.

[DonTZ125]

Definitely weight and body position, with a touch of throttle technique thrown in.

First - as you approach the corner, get your weight on the pegs. I'm not saying LIFT your butt, just make your 'nads happier. Are you hanging off? You shouldn't need to at street speeds, but if you're cracking along... If you hang off, get into position BEFORE you brake - swinging your butt over as you tip in confuses the bike all to hell!

Second - your jetting may be off. You said you have more power since the jetting change, but a too-rich main will hesitate slightly then HIT, leading both to the impression there is more power AND breaking your rear loose.

Third - throttle control. "It happens ... as I am exiting the turn. ... It always happens as i apply throttle though." If you're going through on a closed throttle and then rolling on for the exit, there will very possibly be a 'pop' as the throttle plates crack back open. Throttle technique - throttle is closed under braking approaching the corner; some like to leave it *just* cracked to avoid off/on throttle surge. Start a gentle roll-on AS you start your tip-in, this roll-on does NOT stop until you are ready to roll on harder for the exit. This keeps the rear weighted through the whole turn, and avoids any upsets.

If this doesn't work, you may want to back off the shock one click.

[mrfreeze5]

Definitely weight and body position, with a touch of throttle technique thrown in.

First - as you approach the corner, get your weight on the pegs. I'm not saying LIFT your butt, just make your 'nads happier. Are you hanging off? You shouldn't need to at street speeds, but if you're cracking along... If you hang off, get into position BEFORE you brake - swinging your butt over as you tip in confuses the bike all to hell!

Second - your jetting may be off. You said you have more power since the jetting change, but a too-rich main will hesitate slightly then HIT, leading both to the impression there is more power AND breaking your rear loose.

Third - throttle control. "It happens ... as I am exiting the turn. ... It always happens as i apply throttle though." If you're going through on a closed throttle and then rolling on for the exit, there will very possibly be a 'pop' as the throttle plates crack back open. Throttle technique - throttle is closed under braking approaching the corner; some like to leave it *just* cracked to avoid off/on throttle surge. Start a gentle roll-on AS you start your tip-in, this roll-on does NOT stop until you are ready to roll on harder for the exit. This keeps the rear weighted through the whole turn, and avoids any upsets.

If this doesn't work, you may want to back off the shock one click.

This is always on the street, relatively low speed, 25 or 30mph max! It has happened making a 90* turn, its happened in a curve. Jetting is dead on. I went down one size on the main since I was running rich and spitting and popping about 8K, but thats the only change made. I didnt realize exactly how much power it was robbing though and the bike is perkier in all ranges. There isnt the slightest hesistation now. There wasnt a hesitation before either, but its just smoother through the RPMs now. It was pretty damn fast before given the cold weather, it only gave me problems at high RPM. As far as throttle, its never from a closed throttle. These are partial throttle turns(on 2 occasions from a dead stop making a left turn). I open the throttle more (not WOT, not even close really, maybe 1/2-3/4) as I am leaving the turn. For reference, both times from a stop, left turn, I hit the throttle and the tire slipped as I was entering the outside lane on the street Im turning onto. The bike gives a little shimmy and is happily on its way. Constant throttle or acceleration, I never back off on the throttle in a turn, so its not a bucking or surging problem and the rear suspension should be staying loaded the entire time. And if I am approaching the turn, yes the throttle is usually mostly closed and I compression brake as I set my gear and speed, but by the time I have entered the turn, the throttle is set. I dont like to try to open the throttle after Ive made the turn, it feels unstable. The first time I did it, it may have been the suspension cycling on the soft shock since it was going through an s curve, and it hasnt done it again to the same severity since I preloaded the shock more, which it needed anyway. And that did have a cyclic feel to it. This doesnt feel like suspension anymore though, its too quick, and its only in one direction, there's no rebound feeling to it, it just feels like the back end moves over about an inch. I feel like my speed, throttle, and position are all consistent up to that point where I start rolling on the throttle and the rear end slips just a little before it takes off like a bat out of hell.

I am not certain just yet it is not environmental factors though. The first time it happened, I dont think the tire actually slipped, but the suspension cycled. Fixed that. The second time was on a left turn that I have slipped on before when crossing a portion of the white line on the street, but I thought I missed it this last time. Another time I had passed through a small puddle shortly before going through a light, so that may have played a factor too. And every time but the first time where it shimmied in the S curve on ramp to the highway the tires were still cold.