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Discussion Starter · #1 ·
I tried searching for anything about this, but couldn't fnd any results that helped.

My bike rides straight, and I can't feel it pulling left. But, I have a throttlemeister, and I noticed that if I take my hands off the bars that my bike starts to pull left harder and harder, to the point where I can't even lean hard enough right to make it stay straight. This is a new issue as I have never noticed this before last night. I don't know a whole lot about the geometry of the front end or even if this could cause this. I bought the bike new in 2005, and it has never been dropped. The tires look fine. I even made my friend ride my bike while I rode his so I could look at it, and it looked fine on the rode (except for the tendency to drift hard left).

Do bike shops have alignment machines like a car shop?

Any help would be greatly appreciated.

2005 monster 620 dark under warranty until May. No mods besides tail chop.

Thanks!
 

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Wrap a string around the rear tire & then forward on each side of the front tire. Extend it 1-2 feet in front of the front tire & anchor it. Take a plumb bob & verify that the rear wheel is straight up & down & shim your rear stand accordingly. Now adjust the string so that it just barely skims the front & rear edges of the rear tire & then measure each side of the string distance to both edges of front tire & also check the plumb of the front tire. Most of what you need to know will be visually apparent.
 

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chipazzo said:
First I'd count the tick marks on either side of the swingarm for the chain tension adjustment. If its drifting left, the right side might be further up.
Please dont use the marks on the swingarm for alignment, they are notoriously inacurate. You can use Norms method which works rellay well or you can take a straightedge and hold it against the rear sprocket and sight down the chain. You can get a good idea of alignment by whether or not the straightedge is parallel to the chain.
 

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Mine does the same thing to the right. I've checked alignment of the wheels and all theother stuf like steering head bearings, swingarm play, etc. No reason found. On the track it flicks and turns either direction with no detectable difference. But hands off, and it veers right. I've always thought it may be related to my back - bad disc and my hips don't tilt one way as good as the other.

It could be your body is steering the bike in a way you can't detect if you have an undiagnosed back problem.

You could try standing on the pegs and see if it still does it when you let go the bars. But be careful if you are not used to doing this. I ride on the pegs and steer with body weight on my dual sport bike all the time when in the sand and gravel, so it is a natural way to cross-check the other bike.
 

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Back in the day I had a set of hard swing arm bushings made for a Kawasaki. The machinist made a .030" mistake on the shoulders. That bike always went left if you let go of the bars
 

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Rameses said:
Could it possibly be something as simple as part of the wiring harness or the throttle cable putting slight pressure on the forks?
+1 If you haven't made any changes to the running gear, or dropped it, check this. Always good to do idiot checks first.

Justin
 

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Discussion Starter · #11 ·
Idiot checks, are a good idea, one I rechecked the tire pressure and it was a little low. also I took picks and I need to post but the rear wheel seems to be ever so slightly off in the track. Pardon my idiot speak that is next...

In the track where the rear axle slides so that you can adjust the tension, it appears that the left side is a tiny bt more forward. Not sure if this would cause the biek to drift left. I can fit a key very easily on one side betweent he track and the axle, and can't in the other side.

Thanks for all your suggestions.

BTW, I tried leaving my hands on the bars, and yes this corrects the issues. :p
 

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Mark1305 said:
Mine does the same thing to the right. I've checked alignment of the wheels and all theother stuf like steering head bearings, swingarm play, etc. No reason found. On the track it flicks and turns either direction with no detectable difference. But hands off, and it veers right. I've always thought it may be related to my back - bad disc and my hips don't tilt one way as good as the other.

It could be your body is steering the bike in a way you can't detect if you have an undiagnosed back problem.
Could also be something as simple as the fact that almost all roads are crownen for drainage. (high in the middle and low at the edges). Therefore you're always in a constant if barely perceptible turn, when you take your hands off the bars thereby romoving that steering input, the bike turns.

Try a couple different roads. I have one nearby that leans one way for a while then leans the other way, this will cause you to drift halfway across the pavement. Very disconcerting, especially after several pitchers. [laugh]
 

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GMD Computrack is a franchised bike alignment and suspension tuning business. If there's one in your area, they can tell you if everything's straight or not.
 
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