Rear and/or Front Derailleur recommends

[Rick L]

I'm buying all new parts for my trike and so I'm wondering if anyone has any recommendations as far as the front or rear derailluers. The Shimano Saint series looks neat although I'm not sure these 9 speed units are compatible with a 7 speed freehub. I don't mind spending money on the components as I want this machine to last a long time and it's going to be used in rough conditions :)

Rick L

[Odd Man Out]

Rick

Need more details -- what size cogs on the 7 speed freewheel? A double or triple crankset? What size chainrings? The 9 speed derailers will probably work on a 7 speed freewheel (the 9 speed derailers will offer more range of movement than a 7 speed derailer.) The only thing to watch out for is the size (width) of the chain. 7 speed probably being wider than the 9.

Also, choosing a derailer depends on what type of shifter you choose. SRAM twistgrips are not compatible with Shimano rear indexed derailers and some Shimano trigger shifters are not compatible with SRAM rear derailers. Gettin the drivetrain right was one of the most interesting learning processes for me. Much to learn.

Odd Man Out

[TheKid]

Use components that match. If you have a 7 speed freewheel, use chains and deraillers for 5-8 speed applications. 9 speed chain is indeed narrower than 5-8 speed chain. The side plates are thinner to make it more flexible. Also, more expensive doesn't mean better. Road and race components are not built for rough conditions, and will not hold up to those rigors. Use mountain components instead. That applies especially for cranks. Road and race cranks are geared higher. In rough terrain, especially with a heavyweight trike like the Loderunner, you may need a low gear, or you'll have to get off and push the trike. Sheldon Brown has excellent info on deraillers and proper chain length and adjustment. I have shimano dual control brake/shift levers that are excellent. I haven't seen them online lately, but they cost about $60 for the pair. They include rapid fire shifters, 3x7 speed, and come complete with cables. I learned about them from my LBS owner. They come as standard equipment with mid-range $250 - $500 bikes, like Giant.
I'll be using them on the Hauler.

http://www.sheldonbrown.com/derailer-adjustment.html

Here are some better quality mountain parts:

http://www.jensonusa.com/store/product/FD707A05-Shimano+Xtr+M952+Front+Derailleur.aspx

http://www.jensonusa.com/store/product/RD703A04-Shimano+Saint+Rd-M800+Rear+Drlr+135Mm.aspx
Use the mid-cage for 20" wheels

http://www.jensonusa.com/store/product/CH409A02-Shimano+Hyperglide+8-

http://www.jensonusa.com/store/product/CR407A27-Sugino+Impel+Triple+Crankset.aspx

[Rick L]

Hi,

Here are the stats:
7 speed Shimano Freehub 14-28 tooth
Triple crankset, I'm thinking a Shimano 170mm 22-32-42 unit
Chainring BCD is 64mm
I haven't chosen the chain yet.

I'm going to try to buy the derailleur and compatible shifter at the same time. Mid-cage looks like the size to go for.

Thanks!

RIck L

[Rick L]

Hi

Thanks for all the great info. I was considering only mountain bike components since this won't be a road trike :). The trike uses a 7 speed freehub instead of a cassette. I'll check out those links,too.

Rick L

[n9viw]

Unless I'm mistaken, a freehub IS a cassette-style cluster. FreeWHEELS, OTOH, are different. Which is yours?

[Rick L]

Oops! I meant freewheel

Rick L