noise at rear when applying power

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bladesman73

Über Member
Hi chaps bit of advice needed
Just moved to zonda wheels and upgraded a bog standard shimano rear cassette with ultegra one. Now it seems whenever ive got the bike in the larger three cogs at the back and either go uphill or apply power standing up, i get a bit more front derailleur rub,but also it sounds like rear derailleur rub as well. Is this down to the zondas having more flex than the stock wheels i had on before? I got a merida race lite 904 2013 model.
 
However much the wheels (The rim) flex it won't have the slightest bearing on the hub which will remain rock solid. I'd look at the indexing first.
 
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bladesman73

bladesman73

Über Member
Maybe my mind is playing tricks on me and the noise is just the front derailleur rub?! It sounds different tho..
 
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bladesman73

bladesman73

Über Member
No mate, theres defo noise from front derailleur which is chain rub but almost same sound seems to be coming from rear! As i said only when im in the biggest three cogs at rear and when i up the force..im 92kgs might be the frame flexing?
 
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User6179

Guest
Did you change the old chain when you put on the new cassette , an overstretched chain can add a bit of noise .
 
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bladesman73

bladesman73

Über Member
Yes pal chain changed to ultegra one when cassette changed. Next time im out ill see what happens,it was really windy today so was hard to determine source of the sound
 

Jenkins

Legendary Member
Location
Felixstowe
Zondas are now 11 speed hubs - you're not using a 10 speed cassette without the spacer are you?

Alternatively, is the lock ring done up tight enough or even the QR?
 
This ^^^^
 

bikeman66

Senior Member
Location
Isle of Wight
Hi chaps bit of advice needed
Just moved to zonda wheels and upgraded a bog standard shimano rear cassette with ultegra one. Now it seems whenever ive got the bike in the larger three cogs at the back and either go uphill or apply power standing up, i get a bit more front derailleur rub,but also it sounds like rear derailleur rub as well. Is this down to the zondas having more flex than the stock wheels i had on before? I got a merida race lite 904 2013 model.
Might be a long shot, but I'd check the bottom bracket too. Had a noise coming from (what I thought was) the rear of my bike. Sounded a bit like the derailleur cage was clipping the spokes a tiny bit, and because the noise was most noticeable when I was in the lowest gears at the back, it seemed to add up. However, when I checked it out, the cage was well clear of the wheel. Had the back wheel trued and tensioned, as I thought it could be that creaking and groaning. Still the same!

Working gradually through a process of elimination, and desperation, I moved along the bike to the crank area. Cranks were tight enough, pedals spun freely, but when the BB seemed a bit stiff. Whipped off the cranks and I could barely turn the BB axle by hand. Got the adjustable wrench on it, which got the thing turning, but it felt rough.

Replaced the whole unit with a Shimano UN55 (I know...... old technology, square taper axle) for £9.49 from Wiggle, fitted it..........and "hey presto"...... silent bike!!

I'm now convinced I thought the sound was coming from the rear of the bike as the noise of the rough BB bearings was transmitting through the taught chain (which by coincidence will be at its tightest when in the torque inducing lower gears) and leading me to look in the wrong place initially.

Might not be the issue with your bike, but perhaps worth a look. I know how annoying a mystery noise can be, so worth covering all the bases......even if you think they can't possibly be related.
 
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bladesman73

bladesman73

Über Member
Thanks guys, i got lbs to fit the casette and all spacers required are in place..no play in bottom bracket,however a good suggestion and thanks for ur thoughts..next time im out ill see what happens
 

bikeman66

Senior Member
Location
Isle of Wight
Thanks guys, i got lbs to fit the casette and all spacers required are in place..no play in bottom bracket,however a good suggestion and thanks for ur thoughts..next time im out ill see what happens
I couldn't detect any play in the BB bladesman73, it was just really rough. Might be a total red herring in your case, but worth trying I guess. Good luck! Noises are a nightmare aren't they?
 
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bladesman73

bladesman73

Über Member
Ok just got bike out, one of my 105 pedals has the slightest bit of play. I mean really slight,rocks a little bit when i hold the pedal and rock it,about 1mm..could this be the problem?
 

bikeman66

Senior Member
Location
Isle of Wight
Ok just got bike out, one of my 105 pedals has the slightest bit of play. I mean really slight,rocks a little bit when i hold the pedal and rock it,about 1mm..could this be the problem?
I would doubt the pedal will be causing the noise you have described, but if it has play in it you may as well service the bearings in both pedals anyway. If it does solve the noise then it's a winner...........if it doesn't, then at least you've got another routine maintenance task crossed off the list.
 
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bladesman73

bladesman73

Über Member
Ta pal...weird thing is i have just took the bike out for a hill test,put a hell of a lot of force on uphill..and no noise other than front derailleur rub..wtf! Lets hope it stays that way
 
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