chain stay angle problem?

[rcrampton]

I have an REI Novara Randonee I want to use for loaded touring. It came with road gearing (Tiagra, 30-52T, 11-28T) so I bought a new Deore LX crankset and front derailleur. When I put the new crankset on I can't adjust the derailleur down the seat tube any because the bottom of the cage is alreadt nearly touching the chain stay. So instead of having 1.5mm space between the cage and largest chain ring I have over 1/4". It shifts terribly The same is true if I put a deore LX front derailleur on. I think the root issue is that the frame geometry precludes using a small (22T) front chain ring.

I called the flagship REI store and discussed it with a bike mechanic and from my description he thought I was out of luck gearing it down on the front and suggested I get a cassette with a 32T upper end. This is OK but won't get the gearing low enough for me. He said he hasn't seen other customers try to gear down this bike (which surprises me since it's a touring bike).

Any ideas? Thanks for the help!

 

[boudreaux]

I have an REI Novara Randonee I want to use for loaded touring. It came with road gearing (Tiagra, 30-52T, 11-28T) so I bought a new Deore LX crankset and front derailleur. When I put the new crankset on I can't adjust the derailleur down the seat tube any because the bottom of the cage is alreadt nearly touching the chain stay. So instead of having 1.5mm space between the cage and largest chain ring I have over 1/4". It shifts terribly The same is true if I put a deore LX front derailleur on. I think the root issue is that the frame geometry precludes using a small (22T) front chain ring.

I called the flagship REI store and discussed it with a bike mechanic and from my description he thought I was out of luck gearing it down on the front and suggested I get a cassette with a 32T upper end. This is OK but won't get the gearing low enough for me. He said he hasn't seen other customers try to gear down this bike (which surprises me since it's a touring bike).

Any ideas? Thanks for the help!

Ya using a top swing FD? A 30-52 with a 11x28 isn't a serious loaded touring setup anyway,and that is where the thought process should have started. A 34 big cog is another option as is a 26 or 28 small ring on the original crank.

 

[rcrampton]

Ya using a top swing FD? A 30-52 with a 11x28 isn't a serious loaded touring setup anyway,and that is where the thought process should have started. A 34 big cog is another option as is a 26 or 28 small ring on the original crank.

The mounting bracket is above the cage, so I think that means it's a bottom swing. It appears to swing up as it swings out (9-12 o'clock). It's also a bottom pull.

I bought the bike because I liked the frame, but I knew I would have to regear it later. I *assumed* it would be simple to regear it. Maybe I'll have to go with a 26 or 28 ring and a 34 cog, although I'd rather have a lower gearing than that. The large ring is so big for me that I actually never use it (if I'm going nearly 30 mph I'm going downhill and taking a break, not pedaling!). It's a shame not to take advantage of all 3 rings if possible, maybe I can't.

 

[boudreaux]

The mounting bracket is above the cage, so I think that means it's a bottom swing. It appears to swing up as it swings out (9-12 o'clock). It's also a bottom pull.

I bought the bike because I liked the frame, but I knew I would have to regear it later. I *assumed* it would be simple to regear it. Maybe I'll have to go with a 26 or 28 ring and a 34 cog, although I'd rather have a lower gearing than that. The large ring is so big for me that I actually never use it (if I'm going nearly 30 mph I'm going downhill and taking a break, not pedaling!). It's a shame not to take advantage of all 3 rings if possible, maybe I can't.

Top swing with the clamp below the cage may be the answer.

 

[rcrampton]

Top swing with the clamp below the cage may be the answer.

My wording above might be confusing, or maybe I don't understand the top swing advantage. The problem is that the derailleur cage bottom is bumping up against the chain stay when I lower the derailleur. I have plenty of room left to move the clamp along the down tube further. So I think the fundamental problem is that the geometry of the frame won't allow me to position a derailleur cage low enough to be the right distance from a MTN bike size large chain ring.

 

[boudreaux]

My wording above might be confusing, or maybe I don't understand the top swing advantage. The problem is that the derailleur cage bottom is bumping up against the chain stay when I lower the derailleur. I have plenty of room left to move the clamp along the down tube further. So I think the fundamental problem is that the geometry of the frame won't allow me to position a derailleur cage low enough to be the right distance from a MTN bike size large chain ring.

That is part of the reason behind the top swing design.