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Gearing(8 posts)

Gearingmackgoo
Dec 4, 2001 2:28 PM
I was wondering what people were using for number of speeds. 8sp, 9sp 10sp. I was thinking of sticking with 8sp thinking it wouldn't gunk up as quckly. How about the pros, it seems like some are fortunate enough to get to some races. What are they using?
8-Sp STItriangleforge
Dec 4, 2001 3:07 PM
I'm using 8-speed Ultegra STI for the rear derailleur on my 'cross bike, but that's just because it's what I happened to have in the parts bin. I'm shifting the front with an old SunTour bar-con, but again, it's what I had, and it was easier than stringing up the STI shifter on that side. It's lighter too, with an old DiaComp aero lever on the left, for what that's worth.

I would imagine there are very few sponsored riders who are intentionally choosing 8-speed systems -- and even fewer whose sponsors would actually LET them, since the main point of pro-dealing & sponsoring riders is to help sell the latest & greatest to the paying customers.

I'm also not sure it's much of an advantage, either; I'm running 9-speed Ultegra on my road/race bike, and I like it quite a bit. It's lighter & shifts better than the 8-speed, though not so significantly that I'm hauling out my credit card to junk the 8. I'm not sure you'd notice a significant performance difference in sloppy conditions; nothing that shifts is going to be particularly happy caked up with mud, ice and leaves.

Cheers!
BRAD
I'd say 9 is the most commonclimbo
Dec 4, 2001 4:55 PM
not many races are in full mud anyway, any time I swap a wheel or see anyone else do it, they have 9 speed.
re: 8 speedrpironcladracer (rich)
Dec 5, 2001 8:55 AM
I have 8 and 9 speed possibilities and I run 8 speed, fewer problems shifting. Sometimes 9 speed will misfunction and skip-shift even when leaves get on the cassette. I won't go 9 till I run out of parts.

I'm not happy with 9 speed on my MTB either- think it's best for the road. I have bent the larger cogs on 2 XT cassettes now, have never done that with 8 speed stuff.
8 and 9 speed Shimano same spacingWheels
Dec 6, 2001 10:52 AM
The spacing between the cogs on Shimano is the same for 8 or 9 speed, so the gunk factor diference is really non-existent. I run 8-speed with 9-speed shifters because I have an old hub (126 mm) that will take a 8-speed cog, but not a 9-speed. Remember, the 9-speed cogset is slightly wider than the 8-speed, so you need to have a 8/9-speed compatible hub (130 mm) to run 9-speed.

The Pros typically run 9-speed at the races I have been to.

Wheels
8 and 9 speed Shimano same spacingPNW Cross Rider
Dec 7, 2001 11:34 AM
If 8/9 Speed is compatible with the same hub (which it is) How can the spacing between each cog be the same?? Why does 9 Speed then use a narrower chain?? Why are 9 Speed shifters not compatible with 8 Speed derailleurs?
More On SpacingWheels
Dec 7, 2001 3:55 PM
8-speed and 9-speed aren't exactly the same spacing, but close enough to allow one to shift on a 8-speed cluster with a 9-Speed STI shifter. I know many who either are doing or have done it.

The cog thickness of a 9-speed cog is 1.78 mm, the spacer is 2.56 mm, and the centerline dimension is 4.34 mm. An 8-speed cog is 1.80 mm thick, the spacer is 3.0 mm, and the centerline dimension 4.80 mm. The 0.46 mm differnce between the two centerline dimensions is about 18 mils (the thickness of a piece of colored construction paper) again, not enough to notice any differences in 'gunk' factor the original poster asked. The difference is small compared to the 'slop' in the chain when the shift happens. It's not the optimal set up, and the shifting probably isn't as good as 9-speed STI to 9-speed Cog. The only time the shift is a little sluggish is either when the shift goes from the smallest to the adjacent cog or when the shifting into the largest cog. These are at both ends of the cogset. Other than that, shifting is fine.

I run a 9-Speed Shifter (STI) with a 8-speed 105 cassette. You just don't use either the first shift or the last. It is stll there as in you can click in to it. Mine is set-up so that I don't use the first.

The cassette is on an OLD Ultegra 600 7-Speed 126 mm hub. To fit the hub on my crossbike which has 132 mm spacing, I bought a longer axle, swapped it for the orginial axle, and put a 2 mm washer on each side to take up the slack. The result is a wheel that is centered in the drops and shifts without any problem. Why a 7-speed hub? The dish is less than the 8/9-Speed hub, thus theoretically a stronger wheel and I had it lying around. And, yes a 8-Speed cassette will fit on a 7-speed hub (barely), but a 9-speed won't.

I'll even take it one step further. I bought an old 7-Speed Ultegra 600 RD (RD-6400) and installed on my cross bike. Opened up the Hi and Low Limit Screws and use as a 8 or 9 speed RD. The pulleys are a little thick for the chain and therefore probably wearing quickly, but at $5.00 for the RD, I can afford new pulley's when these crap out. I have never heard of an 8-speed derailleur being not compatible with a 9-speed shifter. The only difference that I know of is the number of teeth on the pulley (11 versus 12).

Check out http://www.branfordbike.com/shimano/shimano.html to get info on what works with what.

Wheels
prosnutz
Dec 7, 2001 1:13 PM
have the latest and greatest stuff courtesy of sponsors, and have 2-3 bikes