Obscure Q: Older XTR der. with Gripshift CX-DT118/128 Compatibility

echelon_john · #1 10-09-2014, 09:47 AM

So, say a guy wanted to run an XTR M951 in an 8-sp setup, using the old Gripshift road shifters.

The shifters came in two models for 8sp; CX-DT118, and CX-DT128. The 118s were spec'd as compatible with Dura Ace rear derailleurs, and the 128s with everything else, including XT.

I'm assuming, then, that the 128s would be the choice for the XTR RD.

Anybody got the knowledge?

kramnnim · #2 10-09-2014, 09:55 AM

I think you are right... http://www.sheldonbrown.com/dura-ace.html

eddief · #3 10-09-2014, 10:02 AM

I used SRAM grip shifters on 9 speed builds. Seems the 2 models in those days were based on one being compat with SRAM rear derailleurs and the other was compat with Shimano rear derailleurs. As I recall the two brands had different pull ratios. I would think, at least in those days, that there was no difference in pull or geo for Shimano road vs mountain RD's.

eddief · #4 10-09-2014, 10:05 AM

Looks as if you are talking about Shimano-branded grip shifters? Don't know nothin about those.

bargainguy · #5 10-09-2014, 10:33 AM

If the Sheldon Brown link above is correct (thanks kramnnim), you could run either shifter with the XTR, just use the alternate cable routing for the 118's. In theory, anyway, no idea how well it works in practice.

echelon_john · #6 10-09-2014, 10:35 AM

Nope--they're SRAM branded. But Shimano compatible.

These:
http://www.ebay.com/itm/Road-bike-ba...item43d0a7e898

Quote:

Originally Posted by eddief

Looks as if you are talking about Shimano-branded grip shifters? Don't know nothin about those.

oliver1850 · #7 10-09-2014, 10:39 AM

Eddie, the GripShift CX-DT series was intended for road bikes. They date back to before SRAM had its own RD design - possibly SRAM's first product(?). Besides the ones mentioned, they had a model for SunTour (which I've never seen).

John: I think you have it right concerning cable pull. The M951 is low normal though. I'm not sure how well it works with GripShift in general. I think the detents in the shifters are ramped differently going in different directions, so you may get overly soft (or stiff) action in one or both directions. An M737/739/750 XT might be a better choice.

Anyone know if SRAM made a low normal specific GripShifter for MTBs?

echelon_john · #8 10-09-2014, 10:57 AM

Thanks. The derailleur in question is high-normal, so I guess it's a 950 rather than a 951.

Mostly wondering if I can use the 118s (easily avail) or need to find the 128s (less so!)

Thanks all. Anybody sitting on a pair of 128s?

Quote:

Originally Posted by oliver1850

Eddie, the GripShift CX-DT series was intended for road bikes. They date back to before SRAM had its own RD design - possibly SRAM's first product(?). Besides the ones mentioned, they had a model for SunTour (which I've never seen).

John: I think you have it right concerning cable pull. The M951 is low normal though. I'm not sure how well it works with GripShift in general. I think the detents in the shifters are ramped differently going in different directions, so you may get overly soft (or stiff) action in one or both directions. An M737/739/750 XT might be a better choice.

Anyone know if SRAM made a low normal specific GripShifter for MTBs?

gdw · #9 10-09-2014, 11:20 AM

Do you know when the shifters were made? Mid 90's? I ask because Shimano used weaker springs in their 8 speed mtb rear derailleurs than their 7 speed models which caused unreliable shifting with Sram's top of the line X-Ray mtb shifters. Various aftermarket upgrades were introduced -the Bassworm, Gore cables, stronger springs- but the shifting was still sketchey and only improved when Sram introduced the Attack/Plasma series in 97 or 98. If those DX shifters are from the mid 90's they might not work well with a 950 derailleur.

echelon_john · #10 10-09-2014, 11:24 AM

Thanks--good point. I believe the CXDTs were right around 1990. I used them back in the day with a DA rear derailleur; they were the 'hot setup' for crit racing in NE before STI.

oldpotatoe · #11 10-09-2014, 11:25 AM

Quote:

Originally Posted by echelon_john

So, say a guy wanted to run an XTR M951 in an 8-sp setup, using the old Gripshift road shifters.

The shifters came in two models for 8sp; CX-DT118, and CX-DT128. The 118s were spec'd as compatible with Dura Ace rear derailleurs, and the 128s with everything else, including XT.

I'm assuming, then, that the 128s would be the choice for the XTR RD.

Anybody got the knowledge?

That is correct but the insides of the shifter is plastic and they do wear.