Front gear issues - help b4 I go insane
Posted: Fri Mar 02, 2007 4:23 pm
I'm on the verge of insanity with this problem. I'm open to any suggestions. I've tried lots of things, but after todays ride, I'm ready to pick the bike up with my oil covered hands and heave it under a bus.
When I first brought my Mongoose Randonneur, the very first time I rode it and shifted down to the smallest chain ring, the chain fell off. The bike is not fitted with a chain anti-suicide plate. I thought "Oh here we go, one of these bikes", but being a new bike, some things needed adjustment as would be expected.
Not only does the chain come off when shifting to the small chain ring, it does it when going onto the large one. I have adjusted the derailleur stops etc.
Now this is what's driving me to insanity. I'm on the middle chain ring and want to change up to the large chain ring, sometimes it will not change up, sometimes it will, and other times the chain comes off. It is the same when shifting down to the smallest chain ring.
I thought this was dependant on where the chain was on the rear cluster, so I have been experimenting with shifting to the relevant front cogs only when the chain is on the same rear cog. I've recently fitted a chain anti suicide plate , so the chain doesn't come off when shifting down, but sometimes the bloody chain won't shift down. Other tiimes it will.
So for example to shift to the small front chain ring, I make sure the rear is on the third largest cog (I've tried all combinations and get the same results) and to shift to the large chain ring I make sure that it is on the third smallest rear cog. The results are different each time, it depends on what mood it is in.
I always back off power when pedalling and move the levers slowly, so it's not my technique. I think the bloody thing is possessed. Here is a list of the original specs and what I have done to it since. I'm still getting the same problems.
The bike came with Deore 9 speed RD, SRAM 8 speed cluster, Sora FD, Sora brifters and Sora cranks with a 30T-42T-52T chain rings. After wearing the bike in and adjusting things, I still had the same problems so I changed the brifters (I don't like them anyway) and fitted Shimano friction shifters. This didn't stop the problem.
Next I changed all of the chain rings for highly expensive stuff and a smaller granny, but the problem persisted. I've just recently changed the cranks for MTB cranks which are Shimano hollowtech with 22T-32T-42T chain rings. I've also fitted the anti-suicide plate.
I am still getting the same problems. I have the stops adjusted and have tweaked them in both directions, but still get 1. no change, 2. does change, and 3. chain comes off.
The last time I had a problem like this I had a cracked chain stay, but this is an aluminium frame and is quite rigid. The BB has no free play, the rear wheel is done up and the cranks are done up tight. The FD is also done up tight.
Anyone have any suggestions?
My options are
1. Change the MTB chain rings for something expensive,
2. Remove the FD stops altogether and really slowly change gears with the friction shifters,
3. Take it to a priest and have an excorcism done
4. Throw the bike under a bus
5. Give up riding
6. Admit myself to a psychiatric institution
7. Suck it and buy a Trek touring bike
8. Suspect maybe a bent link in chain and replace chain?
9. Throw Sora derailleur in bin and fit one chain ring.
PS : This is a long message, don't quote it as the thread will get quite long.
When I first brought my Mongoose Randonneur, the very first time I rode it and shifted down to the smallest chain ring, the chain fell off. The bike is not fitted with a chain anti-suicide plate. I thought "Oh here we go, one of these bikes", but being a new bike, some things needed adjustment as would be expected.
Not only does the chain come off when shifting to the small chain ring, it does it when going onto the large one. I have adjusted the derailleur stops etc.
Now this is what's driving me to insanity. I'm on the middle chain ring and want to change up to the large chain ring, sometimes it will not change up, sometimes it will, and other times the chain comes off. It is the same when shifting down to the smallest chain ring.
I thought this was dependant on where the chain was on the rear cluster, so I have been experimenting with shifting to the relevant front cogs only when the chain is on the same rear cog. I've recently fitted a chain anti suicide plate , so the chain doesn't come off when shifting down, but sometimes the bloody chain won't shift down. Other tiimes it will.
So for example to shift to the small front chain ring, I make sure the rear is on the third largest cog (I've tried all combinations and get the same results) and to shift to the large chain ring I make sure that it is on the third smallest rear cog. The results are different each time, it depends on what mood it is in.
I always back off power when pedalling and move the levers slowly, so it's not my technique. I think the bloody thing is possessed. Here is a list of the original specs and what I have done to it since. I'm still getting the same problems.
The bike came with Deore 9 speed RD, SRAM 8 speed cluster, Sora FD, Sora brifters and Sora cranks with a 30T-42T-52T chain rings. After wearing the bike in and adjusting things, I still had the same problems so I changed the brifters (I don't like them anyway) and fitted Shimano friction shifters. This didn't stop the problem.
Next I changed all of the chain rings for highly expensive stuff and a smaller granny, but the problem persisted. I've just recently changed the cranks for MTB cranks which are Shimano hollowtech with 22T-32T-42T chain rings. I've also fitted the anti-suicide plate.
I am still getting the same problems. I have the stops adjusted and have tweaked them in both directions, but still get 1. no change, 2. does change, and 3. chain comes off.
The last time I had a problem like this I had a cracked chain stay, but this is an aluminium frame and is quite rigid. The BB has no free play, the rear wheel is done up and the cranks are done up tight. The FD is also done up tight.
Anyone have any suggestions?
My options are
1. Change the MTB chain rings for something expensive,
2. Remove the FD stops altogether and really slowly change gears with the friction shifters,
3. Take it to a priest and have an excorcism done
4. Throw the bike under a bus
5. Give up riding
6. Admit myself to a psychiatric institution
7. Suck it and buy a Trek touring bike
8. Suspect maybe a bent link in chain and replace chain?
9. Throw Sora derailleur in bin and fit one chain ring.
PS : This is a long message, don't quote it as the thread will get quite long.