whats wrong with my bike!!!!!!!!!???????AAAAAAAAAAAAAARGH

thehamo

right here it goes.

So I left my bike in to get a total over haul becuase the chain kept on skipping and the crank was making strange noises as if something was snapping. anyway, i got a new chain, new gear cables, new rear cogs, new front forks, new breakpads and the rear deraileur was taken apart and completely overhauled. Bike felt like new, but after a month or two same thing started happening, chain slipping, crank making a funny noise etc. So, got a new bottom bracket (previous one was rusted to bits on taking it out!) and a brand new crank and fited that. Took the bike out for the first time tonight and surprise surprise same thing happening.

IM at a loss as to what can be happening with the bike now. Pretty much everything but the frame is brand new on the bloody thing! COuld it be a problem with the front deraileur maybe? I think its the only part that hasnt been touched on the bike..............

any opinions????

uberwolf

who did this work?

LastGasp

thehamo wrote: »

right here it goes.

So I left my bike in to get a total over haul becuase the chain kept on skipping and the crank was making strange noises as if something was snapping. anyway, i got a new chain, new gear cables, new rear cogs, new front forks, new breakpads and the rear deraileur was taken apart and completely overhauled. Bike felt like new, but after a month or two same thing started happening, chain slipping, crank making a funny noise etc. So, got a new bottom bracket (previous one was rusted to bits on taking it out!) and a brand new crank and fited that. Took the bike out for the first time tonight and surprise surprise same thing happening.

IM at a loss as to what can be happening with the bike now. Pretty much everything but the frame is brand new on the bloody thing! COuld it be a problem with the front deraileur maybe? I think its the only part that hasnt been touched on the bike..............

any opinions????

I don't think it can be the front derailleur. It's only a guide and isn't under any pressure from the chain. The only thing you haven't mentioned seems to be the rear hub freewheel mechanism. http://sheldonbrown.com/k7.html

Dr_Colossus

Wow, sounds like an expensive service replacing all those parts, you must have had serious mileage up on it. I don't understand why you had to get a new fork though, that should last more or less forever.
The original problem sounded like a worn freewheel/cassette. Was the skipping/cracking happening on one particular gear or on all the gears?
Anyway given that the whole drivetrain has been replaced with new parts and that the bike felt like new after the service but now after a month or two the gears are skipping again it just sounds like your gears need adjusting. The new gear cables would have stretched over the month or two since the service making them slightly out of tune and thus skipping between gears. You should be able to adjust the barrel adjusters on the cable housing to make everything smooth again.
Hope it works

petethedrummer

ignore me, i didn't read the post correctly.

thehamo

suppose im just gonna leave it into a bike shop and see what they think about it. The work was carried out by a professional bike mechanic and he did a great job, just didnt fix the original problem I had! Basically I bought the bike second hand and what seemed like a bargain at the time has turned out to be a very costly lesson.

The reason I had to get new forks is apparently the forks were bent back and the mechanic said he was affraid the forks could snap. He gave me the option so I just said sure go ahead.

Gunth

Sorry to hijack this thread but speaking of funny noises do all Planet-X bikes make a ticking noise when in freewheel? Apologies again hamo.

kona

Gunth wrote: »

Sorry to hijack this thread but speaking of funny noises do all Planet-X bikes make a ticking noise when in freewheel? Apologies again hamo.

Thats the ratchet in your freewheel, most make that noise, some are silent.

Nothin to do with the frame.

kona

thehamo wrote: »

right here it goes.

So I left my bike in to get a total over haul becuase the chain kept on skipping and the crank was making strange noises as if something was snapping. anyway, i got a new chain, new gear cables, new rear cogs, new front forks, new breakpads and the rear deraileur was taken apart and completely overhauled. Bike felt like new, but after a month or two same thing started happening, chain slipping, crank making a funny noise etc. So, got a new bottom bracket (previous one was rusted to bits on taking it out!) and a brand new crank and fited that. Took the bike out for the first time tonight and surprise surprise same thing happening.

IM at a loss as to what can be happening with the bike now. Pretty much everything but the frame is brand new on the bloody thing! COuld it be a problem with the front deraileur maybe? I think its the only part that hasnt been touched on the bike..............

any opinions????

My first thought was that you need to get the bike serviced as new parts need to bed in, and usually need re-adjustment.

Its not clear if you replaced the BB and crank or the mechanic did?

What bike is it? If its a full Sus then your bushings could need replacing.

thehamo

no the mechanic fit the bb and crank also after a while. But even still, its the exact same problem that I originally had. Basically, If I try and accelerate from a stop start, up a hill say, the chain will make a clink noise and slip, and I tend to slip off the pedals!

kona

thehamo wrote: »

no the mechanic fit the bb and crank also after a while. But even still, its the exact same problem that I originally had. Basically, If I try and accelerate from a stop start, up a hill say, the chain will make a clink noise and slip, and I tend to slip off the pedals!

Did you check/replace the freehub, thats the obvious part that could be at fault.

Also If your chain doesnt match your cassette then this will happen too(if the pitch of the gear teeth do not match the chain).

Another thing to make sure of is that you derailleur is lined up. The common cause of this is people changing your gears without cycling.

thehamo

right, so was cycling the bike again tonight and the thing was even worse this time. The chain actually fell off the chainrings at one stage and I didnt even touch the gears! it just happend as I was cycling. Could it be that the chain is too big or something? Basically it happens any time I have to put a lot of pressure on the peddals, like starting off on a hill or something, but it also just happens as im cycling on a level surface..........

Mr. Grieves

Does this happen regardless of which gear you are in on the front? If your outer chainring is very worn, your chain can slip or come off completely when you apply pressure, usually causing a load cracking sound. Were the chainrings replaced as part of the overhaul?

If the chain doesn't appear to be sitting comfortably into the teeth of the chainring, but more on top of them, something is worn.

Mr. Skeffington

thehamo wrote: »

right here it goes.

So I left my bike in to get a total over haul becuase the chain kept on skipping and the crank was making strange noises as if something was snapping. anyway, i got a new chain, new gear cables, new rear cogs, new front forks, new breakpads and the rear deraileur was taken apart and completely overhauled. Bike felt like new, but after a month or two same thing started happening, chain slipping, crank making a funny noise etc. So, got a new bottom bracket (previous one was rusted to bits on taking it out!) and a brand new crank and fited that. Took the bike out for the first time tonight and surprise surprise same thing happening.

IM at a loss as to what can be happening with the bike now. Pretty much everything but the frame is brand new on the bloody thing! COuld it be a problem with the front deraileur maybe? I think its the only part that hasnt been touched on the bike..............

any opinions????

Hi there,

If the bike was ok for a month or two after the service I dont think that its an issue with the compatibility of the chain and rear cassette. The cables were replaced so it could be the cables stretching and perhaps the gears need to be re-tuned.

Does not sound like an issue with the front derailleur, sounds like it may be an issue with the rear derailleur or the chainrings could be worn, however you said that the cranks were replaced? Could also be the freehub as Kona mentioned. Its hard to tell without riding the bike, anyway hope you get it sorted, sounds frustrating.

If your chainrings are worn heres what they will look like:


Here is a fairly helpful guide for anyone buying a second hand bike:
http://images.google.com/imgres?imgurl=http://www.camcycle.org.uk/newsletters/36/images/dwg36K.jpg&imgrefurl=http://www.camcycle.org.uk/newsletters/36/article15.html&usg=__Hd0yczSS1_by_H66agaYE7NSW5s=&h=188&w=250&sz=8&hl=en&start=6&sig2=eWntYI9S8Pnrug_2osicCw&um=1&itbs=1&tbnid=1hphQFuhDRXg7M:&tbnh=83&tbnw=111&prev=/images%3Fq%3Dworn%2Bchainrings%26um%3D1%26hl%3Den%26sa%3DN%26rlz%3D1G1GGLQ_ENIE268%26tbs%3Disch:1&ei=rOOWS9-iAuOG4garzIGrCw

If your offered a bike where it looks like the frame or forks are bent, steer clear!

If you want me to have a look at it for you give me a shout.

Cheers,

Skeff

Hungrycol

I had a similar problem. When I applied pressure starting off or went to hoof it there'd be a large crack and my crank would slip a bit. I first thought the chain was over stretched and was not sitting in the sprocket grooves properly but everything looked fine so I replaced the freewheel (the cylindrical thing the back cogs fit on to) and the problems gone.

You might be able to get a cheap whole back wheel for the same price as a freewheel and replacement labour.

Muller_1

Sounds like the freewheel to me, can you get a lone of another rear wheel just to check out if this is the issue

doozerie

Worn parts seems the most likely explanation, as already mentioned. New parts shouldn't have worn down so quickly though, so your freehub could well be the problem.

Another possibility though is that you are choosing a bad gear combination - if there is an extreme chain line from the front chainring to the rear cog that you are in then the chain is more likely to complain when you put pressure on. In severe cases it can cause the chain to skip/slip, and as the parts wear more (which will be accelerated by bad chain lines) this will become more pronounced.

As a rule of thumb, if your bike has a double chainset, don't use the innermost/largest rear cog while in the large ring on front, or the outermost/smallest rear cog when in the small ring on front. For a triple chainset the safest bet is to not use the inner half of the rear block/cogs when in the large front ring, the outer half of the rear block when in the smallest front ring, and the two innermost and two outermost rear cogs when in the middle ring at front. You can often get away with using the "bad" gear combinations but they really do increase the risk of problems, and speed up wear and tear, and as you are already having serious problems you should definitely avoid them entirely.

Other, probably less likely, causes worth checking are:

* Is the top jockey/guide wheel of your rear derailleur too close to, or too far away from, your cogs. Either could cause problems, though typically nothing as severe as you are experiencing. Have a look at the section on B-Screw Adjustment here.

* If your original forks were bent, could the rear of the frame be bent too? Check by eye by seeing if the rear derailleur falls on the same line as the cogs and chain.

thehamo

cheers for the replys guys.
Basically whates brand spanking new on the bike is,

rear sprockets, front chain set, bottom bracket, chain, forks, break pads and cables. The rear derailure was over hauled by a mechanic, (actually Mr Skeffington from this site) only thing that hasnet been replaced on the bike practically is the back wheel its self. So perhaps it could well be the hub. LIke mentioned before, i always hear a loud kinda crack noise and then the chain slips, and last time it came right off. this happened without changing gears, and the chain wasnt too stretched between rear cogs and front chain rings either.

Suppose best bet is to bring it to the LBS and see what they say

feck sake lads

thehamo wrote: »

suppose im just gonna leave it into a bike shop and see what they think about it. The work was carried out by a professional bike mechanic and he did a great job, just didnt fix the original problem I had! Basically I bought the bike second hand and what seemed like a bargain at the time has turned out to be a very costly lesson.

The reason I had to get new forks is apparently the forks were bent back and the mechanic said he was affraid the forks could snap. He gave me the option so I just said sure go ahead.

your frame could be off line , like how did the fork's get bent :rolleyes:
only guessing ,make sure your chain is to the right lenght your derailers are tuned to perfection.
hope you get it sorted.