Front Derailleur moves chain too far over
#1
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Front Derailleur moves chain too far over
Hi all,
I have a road bike with a Claris 2400 triple front derailleur and shifter. I biked perhaps 700 miles on it.
In the largest ring, I have two half-shifting positions (of course). What's puzzling: once I'm in the outer half-shifter position, I can move the shift lever further resulting in the derailleur significantly moving further outwards by 2 to 3 mm. Once, I release the shift lever, the derailleur goes back to the outer half-shifter position.
This causes a lot of misery:
I have to very carefully shift from the middle to the large ring. Once I hear the half-shifter click, I need to stop pushing the shifter further otherwise the derailleur goes into this 2 to 3 mm offset position making the chain slip over the large ring.
This is mostly a problem when I'm on the rear in the outer cogs. When I'm in the inner cogs, the chain does not slip over.
How do I get rid of these 2 to 3 mm?
By now I made a lot of random changes including changing the position of the derailleur. So, assume a completely messed up system :-/.
I have a road bike with a Claris 2400 triple front derailleur and shifter. I biked perhaps 700 miles on it.
In the largest ring, I have two half-shifting positions (of course). What's puzzling: once I'm in the outer half-shifter position, I can move the shift lever further resulting in the derailleur significantly moving further outwards by 2 to 3 mm. Once, I release the shift lever, the derailleur goes back to the outer half-shifter position.
This causes a lot of misery:
I have to very carefully shift from the middle to the large ring. Once I hear the half-shifter click, I need to stop pushing the shifter further otherwise the derailleur goes into this 2 to 3 mm offset position making the chain slip over the large ring.
This is mostly a problem when I'm on the rear in the outer cogs. When I'm in the inner cogs, the chain does not slip over.
How do I get rid of these 2 to 3 mm?
By now I made a lot of random changes including changing the position of the derailleur. So, assume a completely messed up system :-/.
#3
Really Old Senior Member
Try screwing in the H screw about 1/8-1/4 turn at a time and see if you can find a happy balance of not over/under shifting.
#5
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YOu need to set your high limit screw. The FD overshifts to allow the inner cage to push the chain and then drops back when released to prevent chain rub. That's normal operation. The overshift is going too far and pushing the chain onto and then off the big ring. The H limit screw being properly adjusted should prevent this. If the bike is new and under warranty I'd let the LBS adjust it.
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The bike shop who sold you the bike should have caught this at set-up. FD high limit screw. Go back to them and have them do it correctly.
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The bike-store is a virtual bike-store
I played around with the h-limit screw. This has not helped. I played around with "height" of the derailleur on the tube. That has not helped. A combination of both helped.
On the bike-stand (actually I don't have a bike stand - for work/repairs I put the bike upside down) the chain does now nicely move from one ring to the next.
On my test-ride the chain barely moved from the smaller to the larger ring when being in the smaller cogs on the rear: it takes some revolutions for the chain to sit firmly on the larger ring.
This discrepancy of testing things out on the bike-stand vs real world riding makes it difficult to tune the derailleur. Is there a trick to make sure that shifting in the real world behaves exactly as on my make-shift bike-stand?
I played around with the h-limit screw. This has not helped. I played around with "height" of the derailleur on the tube. That has not helped. A combination of both helped.
On the bike-stand (actually I don't have a bike stand - for work/repairs I put the bike upside down) the chain does now nicely move from one ring to the next.
On my test-ride the chain barely moved from the smaller to the larger ring when being in the smaller cogs on the rear: it takes some revolutions for the chain to sit firmly on the larger ring.
This discrepancy of testing things out on the bike-stand vs real world riding makes it difficult to tune the derailleur. Is there a trick to make sure that shifting in the real world behaves exactly as on my make-shift bike-stand?
#8
Really Old Senior Member
The bike-store is a virtual bike-store
I played around with the h-limit screw. This has not helped. I played around with "height" of the derailleur on the tube. That has not helped. A combination of both helped.
On the bike-stand (actually I don't have a bike stand - for work/repairs I put the bike upside down) the chain does now nicely move from one ring to the next.
On my test-ride the chain barely moved from the smaller to the larger ring when being in the smaller cogs on the rear: it takes some revolutions for the chain to sit firmly on the larger ring.
This discrepancy of testing things out on the bike-stand vs real world riding makes it difficult to tune the derailleur. Is there a trick to make sure that shifting in the real world behaves exactly as on my make-shift bike-stand?
I played around with the h-limit screw. This has not helped. I played around with "height" of the derailleur on the tube. That has not helped. A combination of both helped.
On the bike-stand (actually I don't have a bike stand - for work/repairs I put the bike upside down) the chain does now nicely move from one ring to the next.
On my test-ride the chain barely moved from the smaller to the larger ring when being in the smaller cogs on the rear: it takes some revolutions for the chain to sit firmly on the larger ring.
This discrepancy of testing things out on the bike-stand vs real world riding makes it difficult to tune the derailleur. Is there a trick to make sure that shifting in the real world behaves exactly as on my make-shift bike-stand?
#9
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What I normally do is adjust in the stand (a real one) and then test ride taking the tools needed along to make any adjustments on the road as needed.
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Cable tension too taught?
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#11
Really Old Senior Member
[QUOTE=Bashbike;20984477]The bike-store is a virtual bike-store
I played around with the h-limit screw. This has not helped. I played around with "height" of the derailleur on the tube. That has not helped. A combination of both helped........
You didn't screw in the H screw enough. Screw it in all the way and it won't reach the big ring, let alone shift over it.
I played around with the h-limit screw. This has not helped. I played around with "height" of the derailleur on the tube. That has not helped. A combination of both helped........
You didn't screw in the H screw enough. Screw it in all the way and it won't reach the big ring, let alone shift over it.
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