[Lantzman16]

A little help if you would? My sister has taken her pre-owned Felt B16 to two bike shops and they don't have a good answer for us.

Symptom- I can set the B Tension screw (Dura Ace RD-7800 GS) when the chain is on the large chainring 53T and it works well. When I shift to the small chainring 39T the guide wheel rides (hits) on the cassette cogs.

If I turn in the B Tension screw so the small chainring works well, then there is a large guide wheel gap and poor shifting on the large chainring. And the position of the B screw plate is about 90 degrees to the hanger bracket. This angle cannot be correct and hard to achieve.

I've checked the chain length and it seems okay compared to what I've read online. I'm not sure what is wrong. What can I check next?

Felt B16
Dura Ace 10 Speed RD-7800 GS, not original to the bike I assume
The rest of the drive is Dura Ace 10 Speed
53 + 39 Chainrings
28 thru 11 Cassette

I posted this in the Ask Felt thread but could not find it there, so I started a new thread. Any help would be greatly appreciated!

 

[riccardo123]

It seems to me that your issue is setting up the RD, rather than being Felt specific. I would suggest re-posting in the Components/Wrenching section, preferably with a picture. Plenty of people on there know far more than I do...

 

[bikerjulio]

Yes. The Felt angle is irrelevant. I suggest a repost as well.

Post a pic from the side with the chain in the small-small.

When you say "poor shifting" explain in more detail what is happening.

Finally, a check of RD hanger alignment is always in order. My #1 suspicion here.

Also provide some info on the age and wear situation with the bike, chain, cassette.

 

[Lantzman16]

Ah, thanks guys for your help and advice. I will gather pictures and more data and post in the proper forum.