Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 23, 2015 13:45:28 GMT
I've recently started to use my T3a regularly and it's been perfect. Of late it's started to make a clunking sound from the chain/gears when cycling. I presume that everything has bedded in and the chain has stretched thus meaning I now need to re-aligned.
I'm a bit of a noob but was wondering if there's any advice in relation to adjusting the chain, rear derailleur etc...
I've checked and I can't see that the chain is obviously fowling anything. Unfortunately I'm too far away from Decathlon to take her in for her 6 month service.
Is it worth tackling myself or taking to a bike shop?
Thanks in advance
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 23, 2015 14:39:05 GMT
How many miles have you put in on it? Is the clunking very regular? Every pedal revolution etc?
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 23, 2015 15:05:52 GMT
With use the gear cables stretch. This causes then tension on the cable to loosen. If the cable is not tensioned properly then when you shift gear it may be reluctant to shift up or down. This could result in drivetrain noise. It is an easy fix by adjusting the barrel adjuster on the rear derailleur. Turn it clockwise If its struggling to go from big cog to small cog on the rear cassette and anti clockwise if its struggling to go from small to big cog.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 23, 2015 15:53:51 GMT
I've probably only ridden properly for 150 miles or so from new so it really is still very new.
The clunking is on every revolution of the pedals. It's not wheel based and is definitely drivechain or derailleur based.
My first thought was chain stretch but it's not fowling anything anywhere and doesn't seem overly loose.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 23, 2015 15:54:29 GMT
The physical shifting still seems smooth and effortless.
|
|
|
Post by bandit3 on Apr 23, 2015 16:25:24 GMT
Have you checked the crank arms on the bottom bracket are they still tight ?
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 23, 2015 16:29:45 GMT
Check the chain closely for any loose pins which may be out of flush.
Do you have a work stand that will allow you to turn the cranks by hand so you can watch and listen closely for the source of the problem?
|
|
|
Post by Rocket on Apr 23, 2015 19:35:25 GMT
You have isolated the noise to occurring every revolution of the crank so likely candidates are pedals, crank arms loose or my personal favourite - the bottom bracket retaining cups are loose.
|
|
|
Post by r0b1et on Apr 23, 2015 23:03:36 GMT
What Rocket said was exactly the post I was about to make (excepting I don't have a favourite fault!)
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 24, 2015 0:27:42 GMT
Firstly - thank you all very much for your responses and help. Hugely appreciated!!! Well I cycled home from work this evening (literally just) and I could hear the noise over the sound of my musc. Ive been investigating since I got home and I think I've got somewhere... I think Ive got three distinct issues that need my attention. Firstly I think the chain is a little loose causing the bike to be running a little louder than it probably should. The chain is definitely louder than it was when I first got the bike (and Ive been ensuring its kept lubed up). I can't see any loose pins on the chain however I will give it a full inspection tomorrow in daylight. Secondly the bike is definitely more noticeably difficult to change up gears than it was a few weeks ago (not as bad going down but still a definite click). On the way home I was on the middle front gear and changed up one at the back (near the top end of it) which caused it to jolt so badly I had a bit of a large wobble all over one lane (I probably looked like I was drunk!) Its more pronounced at higher speeds. I take back what I was saying earlier about smooth gear changes!! Thirdly Ive been working to locate the source of this noise. I propped the bike up so the rear wheel was off the ground and pedalled slowly and quickly by hand in several gears. How best to describe it... It's like a crunching or grinding. It sounds almost like theres grit being worn down by a ball or like it slipping and seems to be emanating from the bottom bracket. Excuse the ignorance (as I say I am a 100% complete noob) - I'm presuming that the bottom bracket is probably loose and also needs grease? Does the bottom bracket give T3a owners a lot of grief and if so what sort of fixes are there? The bike isn't even 6 months old yet so it seems mad to have these issues (she was in storage until a couple of weeks ago hence the low mileage so far). I've checked the pedals and they are on very tight. I've also checked the crank arms and there's no wobble or lateral movement in them so I think they're fine. I look forward to the responses
|
|
|
Post by Rocket on Apr 24, 2015 7:37:54 GMT
I would take your bike back to a Decathlon store since it is not very old. They should be able to sort this out for free.
I have seen 3 bikes including my own which have loose square taper bottom brackets after very low mileage. After removing and cleaning the grit out of the threads tighten to 50nm and all was well. This will require a crank puller and a bottom bracket tool so unless you already have them try Decathlon.
|
|
|
Post by ChrisD on Apr 24, 2015 8:03:25 GMT
I would take your bike back to a Decathlon store since it is not very old. They should be able to sort this out for free. I have seen 3 bikes including my own which have loose square taper bottom brackets after very low mileage. After removing and cleaning the grit out of the threads tighten to 50nm and all was well. This will require a crank puller and a bottom bracket tool so unless you already have them try Decathlon. Had the same issue Rocket describes with my T3. Guys in the workshop at the local Decathlon had it sorted in no time.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 24, 2015 8:04:16 GMT
I would take your bike back to a Decathlon store since it is not very old. They should be able to sort this out for free. I have seen 3 bikes including my own which have loose square taper bottom brackets after very low mileage. After removing and cleaning the grit out of the threads tighten to 50nm and all was well. This will require a crank puller and a bottom bracket tool so unless you already have them try Decathlon. Agree 100% with rocket on this one. I too had issues with loose BB when i looked at it it could be undone with fingers. Whither it was like that right out of Decathlon or not it hadn't done that many miles. I'm sure if you take it back it'll be sorted no worries!
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Apr 24, 2015 9:21:04 GMT
The issue I face is that my nearest Decathlon store is 1.5 hours drive away in Oxford.... A bit of a trek considering I'm only using the bike at the minute as the car is in for repairs. Ive taken your advice though and emailed Decathlon a short overview and asked how we can resolve the situation. It may end up having to go a local bike shop I guess... Or its a good excuse to buy more workshop tools Is is safe to ride with a loose bottom bracket?
|
|
|
Post by beatnik69 on Apr 24, 2015 9:32:09 GMT
I had the same issue and left my T3a in last weekend. They tightened the BB and the knocking has gone.
|
|