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MTB cassettes on Road bike(20 posts)

MTB cassettes on Road bikeALr
Jan 8, 2002 11:48 AM
Can a person use for example an Xt 12-30 or equivalent size cassette if they want a bigger gear range and dont want to go to a three ring setup. I think if you go to a long cage derailer its feasible. Also, would a Mtb derailler work better with this setup or would a 105 or better derailler work as well. How would this setup shift? Anyone done something similar?
re: MTB cassettes on Road bikepmf1
Jan 8, 2002 12:31 PM
Yep, but you'll probably need a mtb rear derailer. Cheaper than buying triple cranks and a new BB.
re: MTB cassettes on Road biketubs
Jan 8, 2002 2:16 PM
No problem. Often use this setup myself. You dont need an mtb rear deralieur, pretty much all Shimano deralieurs are the same, the difference is in the shifter, with the exception of early Dura-Ace stuff. 9 sp. Dura Ace is fully compatible. So, as long as you use an 8 sp cassette with an 8sp shifter, and a 9 sp cassette with a 9 sp shifter, no problem. You dont need a long cage deralieur either, as mtb stuff is set up for three front rings, while it sounds like you are only using the standard road system with 2 front rings. 8 speed hubs work with 8 or 9 speed cassetts.
re: MTB cassettes on Road bikeSnowBlind
Jan 8, 2002 3:39 PM
campy makes the 10sp in 13-29, but it requires the mid length DR. I am using the 13-26, and it is a damn low gear range, plus I an still swap out a 11-21 if I want to.
Seems high to melaffeaux
Jan 8, 2002 4:59 PM
I have an RSX drivetrain and although I'd like to upgrade, I don't think I can push a Ultegra triple up a steep hill. Right now I have a 24 tooth small ring and 28 large cog (again RSX) and have trouble climbing steep sections (20+% grades). With a 30 tooth Ultegra triple I'm not sure I could handle it.

Are the hills around here just steeper? Sunday I climbed 2,600 feet in 15 miles (the first 8 are pretty flat).
Seems high to megrzy
Jan 8, 2002 5:13 PM
Everyone has trouble climbing 20% + grades - you're mortal. Depending on your fitness a 39/27 combo is condsidered pretty low, but climbing a 20% grade isn't easy. An Ultgra triple can get you down to a 32/27 before you have to go looking for special cogsets and rings.

2,600 in 7 miles is only 7%.

Where do you live?
Seems high to melaffeaux
Jan 8, 2002 9:05 PM
I'm in the SF Bay Area. The hill is not 20% the whole way, just in the steep sections. Most of it is can be climbed in a low gear, but the steep sections are rough even with a 24/28 combo.
Where precisely?Starliner
Jan 8, 2002 10:25 PM
I'm from bay area up north in Terrible Two country. Where is that hill? If something is that steep around here, it's usually a private road off a public one.
Yeah, Where?grzy
Jan 9, 2002 10:28 AM
I'm down in the Santa Cruz area, but have riden the TT and a bunch of other stuff. It's actaully pretty easy to find public roads in the 20% range if you look. Ft. Ross and "the Wall" prior to it is fairly memorable from the TT. Then there's the Pump House Grade on the Climb to Kaiser. Down in the Silicon Valley area we have treats like Bohlman/OnOrbit. Some of the guys I ride with like to seek out the nastiest hills - for fun.
Where precisely?laffeaux
Jan 9, 2002 11:47 AM
This particular hill is Redwood Gulch Road. It starts off of Steven's Canyon Road and climbs to Hwy 9. I take Hwy 9 to Skyline. The section of 9 is steep, but not bad. Redwodd Gulch is probably only a couple of miles, but is tough.

My route is:
Foothills Expy (relatively flat)
Steven's Creek Canyon Road (hilly)
Redwood Gulch Road (very steep)
Highway 9 (solid 3 mile grind)
Skyline Drive (hilly)
Page Mill Road (steep descent)
Foothills Expy (relatively flat)

It's approximately 40 miles round trip from my house.
Hate to break it to you...grzy
Jan 9, 2002 1:49 PM
...., but Redwood Gulch Rd. only maxes out around 17% and that is a very short segement. There are three steep pitches with more moderate sections between. The Western Wheelers had a web page that had all the gory details on all the ugly hills in and around the Bay Area, but things got modified and I haven't been able to find it. It's steep but there are other treats like Hicks Rd., Bohlman/OnOrbit that make Redwood Gulch not seem so bad.

Used to do that very same loop starting from the intersection of Foothill and Stevens Creek where in lived in Cupertino and would sometimes do the Moody Rd. option when presed for time descending Page Mill. If you want to skip the heroics you can take Mt. Eden Rd. to Pierce and then climb Hwy 9.
Ultegra triple=30x27 low gear...nmRusty Coggs
Jan 9, 2002 7:01 AM
nm
re: MTB cassettes on Road bikeChen2
Jan 8, 2002 6:29 PM
We put a 12-34 XTR cassette and XTR rear derailleur on my wife's road bike with an Ultegra triple up front, all 9 speed STI. It shifts just as well as with the original Ultegra cassette, but the ratios are too wide for our area. She doesn't need a 34 cog or a 12 cog. You'll need a mountain bike rear derailleur to run a cog bigger than a 28.
-Al
re: MTB cassettes on Road bikepa rider
Jan 9, 2002 4:03 AM
I'm from harrisburg Pennsylvania and some of our hills are steep. The bike shops are using the MTB cassettes with doubles to help some people from switching to triple.

My one friend commutes and has a 12-32 8 speed with 39/53. He climbs well on steep hills. I wanted to switch to double again and found that 39/32 is almost the same gear ration as my 30/25 range. My friend used a long cage derailer on the rear.

You may need to use an MTB derailer because of the max teeth count. An XT derailer is 34, but my 105 long cage is 29 teeth. The derailer will shift the same regardless of the type of shifters. Touring bikes use STI and MTB derailers and they work fine.

Theirs a web site called SHELDON BROWN GEAR RATIO which you can enter gear numbers to get ratio.

If I did a vacation in West Virginia I would have to stick with a triple because all the hills are 9 to 10 percent grades. That's why they have run away ramps (Snowshoe for example). Our hills are only 3 miles long and steep. I had friend who did montania with a double with MTB cassette and did well.

Hope the MTB cassette works for you. I may try it myself. I see some cassettes for MTB are now 34 teeth.

Go luck
re: MTB cassettes on Road bikeDrD
Jan 9, 2002 4:28 AM
You sure can - just make sure you don't exceed the capacity of your rear der. (a mtb rear der. is not needed) - I think most shimano short cages have a 37 tooth capacity, so if you are running a 39/53 up front, a 12-30 cassette shouldn't be a problem (14+18=32<37) - you could even go with a smaller small ring up front (which actually might be a better choice - the problem with a really wide cassette is that the gears are more widely spaced, which can be annoying - that's the one benefit of something like 10spd which I can see - you can have a wider cassette with the gears more closely spaced - I run a 12-27 and the high end of the cassette ..21-24-27 would be alot nicer if it were ..21-23-25-27 - I am not a big fan of 3 tooth drops!)
re: MTB cassettes on Road bikeChen2
Jan 9, 2002 7:09 AM
The Shimano short cage rear derailleurs (9 speed) do have a chain wrap capacity of 37 but their maximum cog size is 27 teeth, according to specs. I know this can be exceeded but will it really go to 30? I've heard 28 max.
-Al
It's worked for me.12x23
Jan 9, 2002 9:54 AM
I purchased a 'century special' cassette from Harris Cyclery last September to use with my D-A r.der. The cassette was a 'custom' 13x30 and worked just fine. I just had to screw the b-adjustment in far enough for the upper pulley to clear the cassette.
Thanks (nm)Chen2
Jan 9, 2002 11:16 AM
re:Check this.Rusty Coggs
Jan 9, 2002 7:15 AM
Derailers have 2 capacities.Cage length determines chain wrap cpacity, and parallelogram design determines large cog capacity. An ultegra triple long cage wraps more chain,but has the same large cog spec as an ultegra short cage.Current shimano large cog spec for road derailers is 27 teeth, maybe because shimano largest 9 speed road cog is 27. Spec is uasually conservative and they they will usually shift a few more, like probably 30.For large rear cogs over 30 A MTB derailer often works best, but a long cage is not required, unless you need it for chain wrap capacity.
re: MTB cassettes on Road bikeLC
Jan 10, 2002 12:49 PM
I could not get a Ultegra long cage to handle more than a 28 cog. Even with the B-tension screw all the way in, the upper pulley would still hit a 30 cog.

A XT short cage (which is about the same length as a Ultegra long cage) handles a 32 cog with no problem. With the XT it looks like it probally could even handle a 34 cog.