# red - down shifting problems - HELP!!!



## stickystuff (Mar 7, 2007)

have red on my bmc pro machine. group shifts very smooth up/down while riding on flat surfaces. but when climbing and really pushing the pedals when i down shift it is not smooth. sounds/feels like the rear der. is not adjusted properly. i have to constantly trim to get a good mesh. had my mechanic look at it, he saw nothing and shifted fine on his bike stand. he changed out the rear der. cable but still have the same issue. any advice?


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## robdamanii (Feb 13, 2006)

Back off a bit on the pedal stroke when you shift.

Nothing shifts well under hard full power.


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## Kristatos (Jan 10, 2008)

I'd look at the b-adjust to make sure it's in spec. Provided that checks out, the next thing I'd do is adjust the barrel adjuster a little bit. I think you want to turn counter-clockwise to shift up more readily - I can usually only remember these things when I'm actually sitting on the bike. At any rate, I like to adjust it so it's starting to make a bit of noise like it's going to jump up a cog bigger, then back off a bit. Then check to see you can still shift down to a smaller cog effectively and back off a bit more if needed. In general, when I follow that procedure, I can get quick crisp upshifts to larger cogs and the downshift to smaller cogs still works just fine too.


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## UGASkiDawg (Jun 23, 2008)

robdamanii said:


> Back off a bit on the pedal stroke when you shift.
> 
> *Nothing shifts well under hard full power.*


Incorrect...Di2 shifts perfectly in every condition under any kind of power....of course it costs 4 grand


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## robdamanii (Feb 13, 2006)

UGASkiDawg said:


> Incorrect...Di2 shifts perfectly in every condition under any kind of power....of course it costs 4 grand


Ugh, ok, let me rephrase that:

Nothing that us regular joes uses shifts well under full power.


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## Andrea138 (Mar 10, 2008)

How old is your chain/cassette?


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## JSummers (Nov 21, 2008)

*shifting problems*

this is what I have noticed, and I am not a pro bike Mec. and I am not going to name any bike names get that crap started just what I have seen. stiffer bike's have way less problems with shifting under power up or down, then bikes that our not as stiff. All the problems I read on hear about SRAM red making noise while shifting, I cant seem to get my bike to make the noise, its full red, now I don't put out the watts my son does so I put him on the bike and I stand on the side of the street and have him sprint by all I hear is the pop on the gear change thru the carbon wheels. On my sons bike he started with shimano and was all the time having problems with it making noise shifting problems. I would get it all tuned up then day or two later he was saying its making noise, i was asking him if he was playing with it? he would say no. I said that it and switched it out SRAM problem gone. Another reason why I switched him to SRAM, he races and they have SRAM support cars there and they even worked on his bike one time when it still had shimano on it. I am not slamming shimano I know a ton of people that have it and have no problems, but guess what they don't have flex e flyer bikes. sorry not much help here but just figured I would let you know what I have run across


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