Author Topic: wobbly wheel  (Read 12720 times)

Offline Natloz

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wobbly wheel
« on: July 13, 2007, 02:45:05 AM »
I just installed my new 26 inch conversion kit and it runs great except at a higher speed it feels the wheel is out of balance. Should I check the spoke tensions or how can I correct this wobbly wheel?

Offline erdurbin

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Re: wobbly wheel
« Reply #1 on: July 13, 2007, 03:54:17 AM »
If you read my earlier post, I had the same problem. I had to take off the wheel that came with the kit and put my tire on it. The problem was with the tire not seating properly.

Offline myelectricbike

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Re: wobbly wheel
« Reply #2 on: July 13, 2007, 12:28:04 PM »
These are alloy rims and so with your experience of being able to replace the tire it must be the tires. I bought a steel rim for another bike that had sharp internal edges and mounted a Wal-Mart Kevlar tire. The tire would not stay on the rim no matter what I did including inflation of the tube to 110 PSI. A replacement tire worked okay but my first thought was that it was the rim and the guy I bought it from got an earful. I had to apologize when the replacement tire did fine. Sales would probably like an email telling them of the problem.

Offline Natloz

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Re: wobbly wheel
« Reply #3 on: July 13, 2007, 12:29:39 PM »
Thanks for the suggestion, I will try to change the tire.
Another question: does it matter what orientation my battery pack (BT-36-0312) is fastened to the carrier rack? There is no sign on the battery pack indicating which side should be up.

Offline myelectricbike

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Re: wobbly wheel
« Reply #4 on: July 13, 2007, 01:06:22 PM »
Battery orientation is only critical in terms of how hard the surface is the battery is resting on - including the bottom although it is designed to handle the weight.

Offline Natloz

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Re: wobbly wheel
« Reply #5 on: July 13, 2007, 02:47:07 PM »
I replaced the inner tube and tire and no more wobble! About the battery: is it gel or lead acid? Shouldn't worry about leakage if it is upside down? I did notice some fluid coming out at the seams

Offline myelectricbike

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Re: wobbly wheel
« Reply #6 on: July 13, 2007, 07:10:15 PM »
The glue in the seams even after it sets often looks like liquid.

Offline Mordaz

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Re: wobbly wheel
« Reply #7 on: September 24, 2007, 03:04:10 AM »
I'm experiencing some wobbling but it's not the rim, it's the hub motor itself (I got the hub motor only, not a full kit).  It seems the axle is not perfectly perpendicular to the motor casing.  However, the motor works fine.  The wobbling may be an issue at high speeds, though.  Does anyone know how to fix it? 

Offline Mordaz

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Re: wobbly wheel
« Reply #8 on: September 24, 2007, 03:30:56 AM »
I forgot to mention the motor came with no spacers, just washers.  Are the spacers really important?  I mean, does it matter whether the washers are placed against a spacer OR placed against the round part of the axle? 

Now I'm not sure if I should use spacers since the axle is not perpendicular to the motor.

Offline myelectricbike

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Re: wobbly wheel
« Reply #9 on: September 24, 2007, 06:46:17 AM »
Search on the keyword "spacer" under general discussion. Also, you should report your missing spacers and other issues directly to sales.

Offline Mordaz

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Re: wobbly wheel
« Reply #10 on: September 24, 2007, 07:30:44 AM »
myelectricbike,

Just did that and found your post, thanks.  So, is it possible my motor is wobbling due to the lack of these spacers?  Is it necessary that the spacers are compressed against the bearing races for the axle to be aligned (perpendicular to the motor)? 

I'll not complain about the missing spacers.  I'm having some torque arms done, so I'll include some stainless steel spacers in the order.

Again, thanks a million

Offline myelectricbike

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Re: wobbly wheel
« Reply #11 on: September 24, 2007, 09:25:44 AM »
dalecv has reported non-parallel axle flats and Draggin (see: http://goldenmotor.com/SMF/index.php?topic=10.msg1218#msg1218) has reported misaligned axles so we are all concerned that either quality control is not very good or that we are receiving a higher than average number of factory seconds. There should not be enough play between the axles and the races to account for wheel wobble even if they are not secured against the axle shoulders by spacer compression through the washers and hangers by the axle nuts and so a misaligned axle is a more likely cause. Wobble at the rim is normally due to unadjusted spoke length resulting in untrue rims.
« Last Edit: September 24, 2007, 11:01:38 AM by myelectricbike »

Offline Mordaz

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Re: wobbly wheel
« Reply #12 on: September 24, 2007, 03:52:33 PM »
It's definitely a misaligned axle issue, but the motor works fine.  It's probably not as much misaligned as Draggin's.  I hope this does not develop into a serious problem.

This is the second unit I order.  The first is an all black unit, perfectly aligned and working smoothly.  This second one looks better (like the one picture in the gm website), but if given the choice, I'd go for the all black (older?) ones.


Offline Dalecv

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Re: wobbly wheel
« Reply #13 on: September 24, 2007, 04:44:11 PM »
Most likely the spacers on your motor are not extending out past the side cover very much. But they have to be there otherwise you would be tightening the forks up against the side covers and then the motor wouldn't rotate. My spacers didn't extend out past the side covers and I had to add washers to match the width of my forks.

I am afraid the wobble is a quality control issue. Along with wobble in the tire the rim on my motor was also not true. I couldn't fix this because the spoke nuts could not be adjusted. My motor is on a 20 inch wheel and the way they laced up the spokes puts them at extreme angles which doesn't help the situation. They are actually bend at the rim end.

Good luck.

Dale

Offline Mordaz

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Re: wobbly wheel
« Reply #14 on: September 27, 2007, 04:57:11 AM »
Most likely the spacers on your motor are not extending out past the side cover very much. But they have to be there otherwise you would be tightening the forks up against the side covers and then the motor wouldn't rotate.

I was tightening the forks against the end of the flats in the axle, with the provided washers in between.  I did not receive any spacers.  I'll have some spacers made out of stainless steel and will not use the motor until I have these spacers.