Smallguy

hi I have a fairly nice mtb bike trek fuel ex 9 form 07 and I've noticed that my Giant OCR 1 shift allot better under load

I'm always semi concerned about shifting my mtb on a climb but my road bike shift easily on climbs where my mtb will clunk and I've busted a few chains this way as well

anyone else notice this and why is it the case ?

Siu Blue Wind

Are you shifting while pedaling hard uphill?

ed 

Probably because the gear ratio's are closer together on a road cassette.

Siu Blue Wind

I'm thinking the chains are breaking because of heavy load shifting. Surprised chainsuck hasn't occurred.

ed 

YOu're not supposed to shift on a climb under load...you need to surge forward, soft pedal as you shift, put the power back down when the chain drops on the cog.

Shifting under a load is a bad idea on any derailleur'd bike.

roccobike

Keep shifting that OCR1 under hard loads and watch what happens. 105 STI shifters are really nice, but you'll damage your chain and cassette if you continue to shift under hard load.

born2bahick

I shift under load constantly, Mine works fine XTR RR, and Low normal, Sram XO, And Deore lx setups.
All shift fine under out of the saddle attacks if need be? I think the OP should check indexing, Cables, Housings and shifters.

Siu Blue Wind

Yep. ^^^ That was my point.

born2bahick

Why? If you need to shift You should be able to? shouldn't you? Cmon Ed Big Blanket
Ohhhhhh And Quit pushing my wife down!

victim

My OCR 1 with 105 gruppo shifts better than my x9 bike and my XT/XTR bike. Never really thought about it until now, thanks...

Siu Blue Wind

When you are shifting under load and the chain hasn't had the chance to seat then you are forcing the chainring to move when at that teeny moment there is no chain on it. The chainring will purge forward, the chain won't catch and you get chainsuck because it jumps and gets caught in between the frame and the chainring or in the chainring itself.

born2bahick

I haven't had any problem with experiences like that. Maybe the bike gods are shining on me.

Smallguy

it's not something I try to do and even if i do I try to be genital and ease up on the pedals but sometimes after allot of climbing my legs are burning and I need a gear I can spin easier

I just notice my road bike handles this much better than my mtb bike even though my mtb bike has a pretty top shelf drive train and 105 is "middle of the road"

born2bahick

Ed's a good wrench fo sho, He's putting more power to the pedals evidently, Siu too, for that matter. I must be a wuss.He He