Bicycle Mechanics - Gripshift with a Shimano derailleur, troublesome?

A friend of mine has some problems with shifting on his bike. The shifters are Sram Gripshift and the derailleur is a lower-end Shimano. We went to the LBS and two guys there told that shifting troubles with the Sram Gripshift and Shimano derailleur combo is a common problem that can't really be solved because there is 10mm play in the correspondence between the parts. :(

Can anyone confirm this? And what can be done about it?

That used to be a issue say 8 to 10 years ago. Now that should no longer be a problem. The first thing I would say is to check the length of the housing at the der. All housing should follow the natural curve of the housing. If it is too long at the der then you will get sporatic shifting. A good site to look at this stiff for yourself is here:
http://www.parktool.com/repair_help/index.shtml

There is also a 1.1 mm cable that offers a little less resistance and improved shifting.

A friend of mine has some problems with shifting on his bike. The shifters are Sram Gripshift and the derailleur is a lower-end Shimano. We went to the LBS and two guys there told that shifting troubles with the Sram Gripshift and Shimano derailleur combo is a common problem that can't really be solved because there is 10mm play in the correspondence between the parts. :(

Can anyone confirm this? And what can be done about it?

There's lots of different Gripshift shifters. Did all of the parts come on the bike when it was new? If so, then it's just a matter of figuring out what's wrong. Since attempts have already been made to improve the shifting, I'd start by checking the derailleur alignment.

If either the shifters or derailleur have been replaced somewhere along the line, be aware that ESP Gripshift shifters will only talk to ESP rear derailleurs because the cable pull ratios differ from Shimano. I wonder if that is what your LBS is talking about.

Finally, you mentioned that your friend has a low end Shimano derailleur. My experience has been that low end derailleurs work better when matched up with low end Gripshift shifters. I think that the cheaper Gripshifts have a little bit of play in them that allows you to "overshift" the derailleur a bit and then allow it to drop the chain back down into the next cog.

Good luck.

be aware that ESP Gripshift shifters will only talk to ESP rear derailleurs because the cable pull ratios differ from Shimano. I wonder if that is what your LBS is talking about.

Yes, they mentioned the cable pull difference between the two brands. What is ESP?



I think that the cheaper Gripshifts have a little bit of play in them that allows you to "overshift" the derailleur a bit and then allow it to drop the chain back down into the next cog.

That's exactly the problem. He has to 'overstretch' (or overshift like you call it) the grip all the time to help the chain fall onto the next cog. It's quite irritating because it takes too long and sometimes leads to sore wrists after extended riding. Also, when he shifts from the middle ring to the large one (or vice versa) and shifts to another cog as well there's this noice like everything is going wrong.

If your friend is using ESP shifters with a shimaNO der, I would question whoever it was that sold him that combo for they should know better.