Team-BHP - RE Thunderbird TBTS - Rear wheel issue (noise, wobbling)

Hi Guys,
I am facing the following issue in my 1800km run TBTS. Please help.

There is a noise coming from the rear wheel hub that sounds like metal being bent and released, like a 'clunk' kind of sound.

I started seeing this a couple of days after I got my bike back from service (Teknik Motors, Sarjapur Rd).

Other symptoms -
- I feel like there is some friction at a certain point in the wheels rotation, I can feel that certain rubbing when riding too. When I apply rear brake, I can feel it a little more
- in slow speeds, there is a hint of rear wheel wobble
- chain sounds like that of a cycle being pushed

When I first took it back to Teknik, they said wheel was bent, so I got that rectified from another place. Second time, they claimed not to hear anything unusual (the service shop is on a very busy road). I also complained that the chain was too noisy but they said this is how it is and it will reduce over time.

I have recorded the sound and uploaded a video, please have a look and help me diagnose the issue. If I can get an idea of what is wrong, I can deal with these guys better.

Video -
http://www.youtube.com/watch?v=Vse5B64JKvo

I suggest you check the entire tire path. Is it touching anything like the mud guard, the chain guard and so on.

Also remove the wheel and inspect the brake shoes. You can do this yourself. Its very easy to remove the rear wheel and fix it back. Unlike the front wheel.

Quote:

Originally Posted by datvichrox2 (Post 2624861)

Other symptoms -
- I feel like there is some friction at a certain point in the wheels rotation, I can feel that certain rubbing when riding too. When I apply rear brake, I can feel it a little more
- in slow speeds, there is a hint of rear wheel wobble
- chain sounds like that of a cycle being pushed

When I first took it back to Teknik, they said wheel was bent, so I got that rectified from another place.

I have usually seen the following two factors causing the wobble:

I. The RIM had a hard hit due to which it is no longer symmetrical and this can cause the wobble. But in you case as you have indicated that the RIM was repaired so this should not be the cause.

II. The side wall of the tyres are not set-up symmetrically. Usually after a puncture when the tube is repaired and inserted back into the tyre and then inflated the side wall of the height of the sidewall may have different length at different location within the tyre circumference. This can cause the wobble. Take you bike to a type show and have them check this.

Please check for the following first to rule out things one by one:
1. Check the rim/ tyre side walls for any rubbing signs. I don't think there would be any.
2. Look closely at the chain for metal rub - open the crank chain cover and see if you still hear the sound? Check the crank and wheel sprockets for a bent/ chipped cog.
3. Take off the chain guard and see if you still get the sound.
4. Get the rear brake drum opened and check for a missing nut.
5. Check the rear wheel bearing assembly for any play / misalignment.

Let us know how it goes.

Note from the Team-BHP Support Team: Please avoid quoting an entire large post. It inconveniences our small screen & mobile readers.

Quote:

Originally Posted by SwiftSD (Post 2625154)

II. The side wall of the tyres are not set-up symmetrically. Usually after a puncture when the tube is repaired and inserted back into the tyre and then inflated the side wall of the height of the sidewall may have different length at different location within the tyre circumference. This can cause the wobble. Take you bike to a type show and have them check this.

Excellent Point.

To check this you don't need to go to any specialist.
There will be a line that is present and it runs along the entire length of the tire. This line is quite prominent.
Its distance from the rim must remain equal at all places.

Quote:

Originally Posted by bblost

Imran - I feel there is a definite clunk in the video - metal against metal.
Don't think it would be a tyre wobble issue as in the video the bike is mounted on the main stand.

No harm checking the edge of the rim for a rub mark.

After seeing the video, I felt that chain is hitting something -- can be chain cover -- and that is causing the noise. Is the chain cover loose, if it is, then that can hit the wheel also.
Check the wheel alignment also. And see if the wheel bearing are not worned out.

Thanks for the inputs guys!

I checked for rub marks, couldn't find any on the chain or the tire. The side wall of the tire seem to be correct - they are equal all round. Next thing would be to take off the tire and chain guard.

Ill keep you guys posted. Thanks again!

Would like to add that the metal sound is coming from within the wheel hub. Also any thoughts on chain noise? I can hear the chain when Im riding (when not accelerating)

Quote:

Originally Posted by datvichrox2

Would like to add that the metal sound is coming from within the wheel hub. Also any thoughts on chain noise? I can hear the chain when Im riding (when not accelerating)

I have a hunch the noise is from within the brake drum or wheel bearing.
Like bblost has already said; avoid riding the bike till the issue is sorted.

The chain noise is normal; just check for optimum tension as per your manual; get it washed and put a few drops of engine oil - no grease. You should be fine.

I'm not able to view the video (am at work) but is the "clunk" happening when u open/close the throttle? If so, try taking a look at the cush rubber on the rear sprocket, it might be worn/damaged.

The constant rubbing being amplified during braking seems like mis-aligned/loose brake shoes. Not sure of the exact setup on the Thunderbird, so cant comment further. Take off the wheel and inspect for any unusual scuff marks. Can wheel alignment go wrong on a Thunderbird when tightening the chain etc? Am asking because it happens on the Yezdi unless done carefully.
Before getting at anything else, rule out a bad wheel bearing first. Its surprising how often this is overlooked.

Cheers
Rahul

Hi Vimal, Is it a misaligned brake plate issue? (the brake shoe touching the sides of the drum) Just try loosening the castle nut, stub axle nut, brake anchor nut etc..have some one push down the brake pedal hard and retighten all the nuts. The worse senario could be a detatched brake shoe liner and in that case be careful when you ride the bike as the wheel would lock up all of a sudden.
Regards Adrian

Sounds similar to misaligned chain, biting & slipping off a few sprocket teeth. same with kinky or too tight chain. You can remove chain to confirm source. if its from hub, try back plate centering as in adrian's post. Also removing the wheel lets you have peek into drum thru sprocket slots. Iirc some early Uce's had issues with brake shoe springs binding/ rubbing the drum.

Thank you all, for suggestions!

The problem has been identified. I took the bike to the service center multiple times last week and finally today they opened the wheel and checked.

Last couple of visits was spent on making the mechanics understand the issue. I took the video on my phone and made them hear using headphones. And even after that they only loosened the chain and applied grease to the chain. And still claiming to feel no rubbing or strange vibrations.

So today one of the senior mechs took my bike in and by evening we came to know that the wheel hub was faulty. Turns out that there's a bump on one of the surfaces of the hub and they have seen it before on other vehicles, but its a very rare case.

So I'll be getting a new part (under warranty) in about 10 days, just in time for the second service.

The mech said he put in a different wheel to check and found that the problem went away.

I tried to remove the wheel myself last week, but I just could not get the axle out, it was that hard and I dont know if it is supposed to be like that. So I resorted to the headphone plan!

Oh and again they said the chain was too tight when they themselves had loosened the chain three times on prior visits (different mechanics)

-Vimal