Chain drop constantly

[jowwy]

 

[RecordAceFromNew]

Instead of / in addition to posting a pic of the bb, what is the chainline? It is the distance from the centreline of the frame to the middle of the two chainrings. Should never be more than 50mm.

 

[jowwy]

Instead of / in addition to posting a pic of the bb, what is the chainline? It is the distance from the centreline of the frame to the middle of the two chainrings. Should never be more than 50mm.

not at home at the moment but i would guess its at least 75mm from centreline of frame to centre of the two chainrings

 

[jowwy]

Update:

went into my lbs in abergavenny showed him the picture and spoke about my problem.

he also says that the bottom bracket looks to big, so its going into the doctor's tomorrow for a new bracket and gear rebuild and this on a bike thats only 6 weeks old.

who's idea was it to take up cycling

 

[RecordAceFromNew]

6 week old bike with wrong chainline? Interesting. What bike is it, where does it come from?

 

[jowwy]

Its a raleigh team sprint from rutland cycles - chainline using the website http://www.parktool....inline-concepts

having done all the measurements as they have said, my chainline should be 45mm, its measuring close to 60mm

it does seems odd, but as well as throwing the chain off the bottom, its also difficult getting the chain onto the top ring too, the mech seems to have to travel a long way and the adjustment screw is fully out on the H.


this is the link to the bike

http://www.raleigh.co.uk/ProductType/ProductRange/Product/Default.aspx?pc=1&pt=14&pg=5963

 

[Angelfishsolo]

Update:

went into my lbs in abergavenny showed him the picture and spoke about my problem.

he also says that the bottom bracket looks to big, so its going into the doctor's tomorrow for a new bracket and gear rebuild and this on a bike thats only 6 weeks old.

who's idea was it to take up cycling

I agree. That bottom bracket is wayyyyy to long. Prob by half an inch or more. New BB problem solved

 

[zexel]

I know it's not necessarily the problem jowwy but just wanted to say I agree with what Globalti said 100%

3mm shouldn't matter, the important point is that there is nowhere for the chain to go. If you look at the picture I posted of the K-Edge, the gap is about 2mm. Have you actually tested it?

With these 50-34 compact chainsets I'm pretty convinced that technique has little to do with it. I tried to live with the problem for a couple of frustrating months before I fitted the K-Edge, during that time I tried all kinds of different combinations of speed and power. The problem was that the shifters would throw the chain across pretty abruptly and it would just carry on past the small ring. It was completely random but would happen about once in every three shifts so was a big annoyance when out riding with a buddy.

 

[jowwy]

I know it's not necessarily the problem jowwy but just wanted to say I agree with what Globalti said 100%

i have purchased the n gear jump stop - so will fit that after the new BB as been fitted for extra security.

 

[RecordAceFromNew]

Its a raleigh team sprint from rutland cycles - chainline using the website http://www.parktool....inline-concepts

having done all the measurements as they have said, my chainline should be 45mm, its measuring close to 60mm

it does seems odd, but as well as throwing the chain off the bottom, its also difficult getting the chain onto the top ring too, the mech seems to have to travel a long way and the adjustment screw is fully out on the H.


this is the link to the bike

http://www.raleigh.c...1&pt=14&pg=5963

Am not sure whether you got the bike directly from Rutland or the lbs, either way if I were you I would contact supplier and ask them to pay for the fix (and hopefully fix all they have supplied!). 60mm is an absolutely ridiculous figure for chainline given there are industry standards for such things (see this) so that components can work as designed.

 

[2old2care]

That is deffo the wrong btm bracket!!!

 

[jowwy]

My bike is now back from my LBS - the bottom bracket was 122mm and a 110mm should have been fitted £35 out of pocket

and i have sent two stinkng emails one to rutland cycles and one to raleigh.

as yet after 3 days i have received nothing back from rutland cycles not even a confimation email.