Has anyone regeared a Twinn to put a hill climbing gear on it for
real
Quoted message said:
slow riding. I'm wondering if I should try putting a different gear cassette on the back...one with a larger set of gears. Or, should I
try
Quoted message said:
swapping one or both of the front gears with smaller ones.
That's going to be tough. All you can change easily is the rear freewheel. I'd recommend a Shimano 14-34 freewheel: http://harriscyclery.net/site/page.cfm?PageID=49&SKU=FW8134 You may have to install a rear derailleur with a longer cage in order to get to the big cog. You will probably have to buy an adaptor "claw" in order to mount a newer rear derailleur on the Twinn's stamped dropout.
I don't think you'll be able to put a smaller front chainring on the Twinn without radical adaptation. The Twinn chainrings were unique (in order to fit two chains on chainrings on the one-piece cranks) and, AFAIK, there were no other sizes available for the 5-speed.
The "radical" method would be to install three-piece cranks on adaptor bottom brackets. You'd still be limited to one or two chainrings (since the timing chain is on the right). 110mm bolt pattern cranks would probably be your best bet- 34 tooth timing rings and 36 to 46 tooth driving rings would be my thought. Even this will require a bunch of fiddling to get the spacers arranged appropriately.
Thanks for the ideas. I saw what you meant about the chainring change being the hard approach. I ended up using your suggestion and changed the freewheel. The lowest gear on the Suntour freewheel I bought (NOS from the early 80's) has 38 teeth! That's a big cog. I used a big old derailleur that just makes it over the log gear with a little space to spare. It rides real nice...this new hill climbing gear makes moving this heavy bike easy.
- Michael
JeffWills said:
Quoted message said:
Has anyone regeared a Twinn to put a hill climbing gear on it for
real
Quoted message said:
slow riding. I'm wondering if I should try putting a different gear cassette on the back...one with a larger set of gears. Or, should I
try
Quoted message said:
swapping one or both of the front gears with smaller ones.
That's going to be tough. All you can change easily is the rear freewheel. I'd recommend a Shimano 14-34 freewheel: http://harriscyclery.net/site/page.cfm?PageID=49&SKU=FW8134 You may have to install a rear derailleur with a longer cage in order to get to the big cog. You will probably have to buy an adaptor "claw" in order to mount a newer rear derailleur on the Twinn's stamped dropout.
I don't think you'll be able to put a smaller front chainring on the Twinn without radical adaptation. The Twinn chainrings were unique (in order to fit two chains on chainrings on the one-piece cranks) and, AFAIK, there were no other sizes available for the 5-speed.
The "radical" method would be to install three-piece cranks on adaptor bottom brackets. You'd still be limited to one or two chainrings (since the timing chain is on the right). 110mm bolt pattern cranks would probably be your best bet- 34 tooth timing rings and 36 to 46 tooth driving rings would be my thought. Even this will require a bunch of fiddling to get the spacers arranged appropriately.
Thanks for the ideas. I saw what you meant about the chainring change being the hard approach. I ended up using your suggestion and changed the freewheel. The lowest gear on the Suntour freewheel I bought (NOS from the early 80's) has 38 teeth! That's a big cog. I used a big old derailleur that just makes it over the log gear with a little space to spare. It rides real nice...this new hill climbing gear makes moving this heavy bike easy.
- Michael
Ah, so- you have found the *one* exception to the "34 teeth is the biggest freewheel cog anywhere" rule: http://www.firstflightbikes.com/_borders/RaleighTRRD.JPG AFAIK, only the Suntour AG derailleur works well with this freewheel. Your derailleur probably makes it with a smidgen to spare.
-- "Bicycling is a healthy and manly pursuit with much to recommend it, and, unlike other foolish crazes, it has not died out." -- The Daily Telegraph (1877)
-- "Bicycling is a healthy and manly pursuit with much to recommend it, and, unlike other foolish crazes, it has not died out." -- The Daily Telegraph (1877)
