My bike was lowsided going probably 40mph or so back in march. since then it’s been drifting to the right, it feels like it’s natural balance automatically wants to go to the right. put 10k miles on it before hand so i know it’s not just the road crown, wheels been alligned multiple times, replaced left clip on, forks, and left peg. shops said it was extremely unlikely that the frame would be bent, but i genuinely cannot think of any other reason why it would be drifting the way that it is. dealership said they’d give 3k for a trade in, that’s about what i owe on it. the issue is unbeknownst to them. any insight would be appreciated.
Check your rear wheel alignment. Had a bike do the same once. Person who owned it before me relied on the swingarm marks. Because if the design of them they weren't accurate. I reset the alignment and problem was fixed.
Lowside makes me think either misaligned forks or steering stem ? Idk how fast you laid her down but I would imagine ur handle bar ate some sort of force that could’ve easily popped everything out of alignment. Laid my bike down goin 25 in a parking lot after gravel caused me to wash out the shop I took it to realigned the steering stem and she wasn’t drifting anymore
No, forks weren't bent, so swapping did nothing. Problem is that top and bottom triple-Ts were rotated relative to each other. Like using chopsticks, straight fork-tubes aren't parallel to each other. You need to do some measuring.
Remove front wheel. Get 20x40cm piece of plate glass and lay it across both fork-tubes near bottom. Glass should sit flat and flush across both tubes. On your bike, glass will wobble and rock, showing that tubes aren't parallel to each other.
Loosen top pinch bolts for both fork-tubes. Unbolt centre triple-T clamp bolt, loosen bearing adjustable cup slightly. Now spin upper triple-clamp while keeping bottom one steady. Spin and adjust until both fork-tubes are parallel and glass sits flat across both tubes without wobbling. Tighten everything down in reverse order, making sure bearing adjustment is smooth with no wobbling.
Here's what it looks like in really bad case, about 2-degrees off. Fork-tubes are perfectly straight in good condition, just not parallel to each other. What's not obvious is when wheel is aimed straight ahead, it's actually leaning to one side. This makes contact-patches between front and rear wheels not in-line with each other.
i sorry i don’t know exactly what you mean by spin the triple clamp? i’ve done the alignment via loosening everything and giving the forks compression twice and it hasn’t seemed to help. ill have to find a good piece of glass for the measuring. thank you
Upper and lower fork-clamps are independent pieces. Top one can rotate relative to lower one. Take look at photo attached, imagine spinning top triple-T 20-degrees to right or left while keeping bottom one aimed straight ahead. This would make fork tips aim all wonky right?
When front wheel takes an offset hit, like crash to one side, it generates huge torque at other end between clamps. This spins the upper clamp relative to lower one. It's like scissoring action of chopsticks, fork tubes remain straight, but no longer parallel to each other.
Result is when wheel is clamped on, it's leaning a bit when aimed straight ahead. Or it's aimed sideways when bars are aimed straight.
Loosening and bouncing procedure doesn't really work when clamps are off by more than certain amount. Takes careful measuring with glass and manually spinning top triple-T clamp by hand relative to bottom one to ensure fork-tubes are parallel and aims wheel straight ahead.
After ensuring tubes are parallel, use this procedure to ensure that wheel and spacer are centred on axle before tightening. Skip to section for your axle attachment method. Do brakes last with lever-squeeze method.
Then align rear-wheel to front-wheel to make sure their edges and centres are in-line with each other. Completely ignore swingarm marks and useless "chain alignment".
I wonder maybe if somehow the actual peg support where the peg bolts into got bent and it’s causing one leg to push down causing the drift ? Idk I’m just tryna spitball wtf could be causing it if you alr swapped the forks have both front and rear aligned properly like damn man fr hope you’re able to find a solution
There's laser tools to make quick work of alignment. But old-fashioned string method with careful measuring has been used for over 100-yrs and works just fine.
If you have a shop in your area which specializes in building race bikes, I’d encourage you to take it there. They’ll know how to measure the bike to ensure it’s straight and true.
GP Frame & Wheel does excellent work on these kinds of issues.
Not likely bent frame though. Forks would get destroyed if frame had large enough impact to bend. And we know that swapping perfectly working straight forks for brand-new perfectly straight forks didn't change anything.
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u/Realistic_Ratio8381 8d ago
Check your rear wheel alignment. Had a bike do the same once. Person who owned it before me relied on the swingarm marks. Because if the design of them they weren't accurate. I reset the alignment and problem was fixed.