Changing a triple
 

Apologies if this topic has been covered before, but right now the Search function is not working for me.

I'm running a 44-34-22 triple, but will change to a 52-42-30 soon. What issues might I face using the same front derailleur?

An unrelated question. Is it possible to get an 'extra' click out of an indexed front gripshift designed for a double, so that it can be used on a triple?

Thanks.

1. The arc of the 52 chainring will obviously be significantly bigger than the arc of the 44. Assuming that you're using a front derailleur that was designed for use with a max 44 or 46 chainring, you're going to have trouble because the arc of the derailleur cage will be too small to match the chainring. You'll find that you have to install the derailleur way high up on the seat tube and it won't shift well.

Installing a front derailleur that's designed to work with a 52 chainring may not be so simple either. All of the road derailleurs that I'm aware of are downpull and require under the bottom bracket cable routing. If your bike was designed for use with a top pull derailleur, the cable stops will be in the wrong place.

The front Gripshift thing is a trick question. I'm not aware of any indexed 2 position front shifters. If such a thing does exist, it would be beyond the ability of a home mechanic to convert it to 3 position. If it isn't indexed it'll work fine.

I'm wondering why you want to make such a drastic change. Mixing road components with mountain bike components works well in the rear of the drivetrain, not so well in the front.

Also check to make sure the large ring doesn't contact the chain stay!

You can use a cable pully to switch the direction to a downpull. I put a campy daytona group on a cross bike that used an up pull FD. I added the pully wheel and it has worked perfectly well for a couple of years with no signs of quitting. I went to Performance Bike and the mechanic and I looked through a catalogue until we spied something that worked. $15 or $20 is the number that sticks in my head.

Actually, it's all a little complicated. Originally it was a 44-34 double on a twenty inch wheel bike. It then became a 44-34-22 triple on a standard size bike. Now I've decided to go back to the twenty inch bike again, but this time with some more useful gearing - the 'large' 52 tooth chainwheel will give about a 95 high, while the 30 tooth will give about 20 for a low.

I may live with the less-than-perfect shifting, providing it actually shifts and doesn't throw the chain off or chew it up. Thanks for drawing my attention to this.

Fortunately, the bike in question has under the BB routing, so no special problem there.

Sorry. My mistake. Until recently I'd never used anything other than friction levers, so my knowledge of indexing is zero. From what you say, therefore, I assume that the front Gripshift works on friction and should accommodate a triple?

Ahh! I hadn't thought about that. Is there a formula to work with or do I have to eyeball it?