I have a fitness bike with a flat bar and Claris 2x8 shifters and drive train on it. I would like to convert it to a road bike by swapping the handle bar and its shifters with another one that comes with the Shimano Claris 2403 (8x3) on it. Are these compatible, or can they be adjusted so that they can be used with the 2x8 drivetrain?  Senior Member Join Date: Dec 2014 Location: Catalonia Posts: 949 Bikes: Canyon Grand Canyon AL SL 8.0, Triban RC520 Gravel Ltd, Btwin Ultra 520 AF GF, Triban Road 7, Benotto 850 Mentioned: 1 Post(s) Tagged: 0 Thread(s) Quoted: 401 Post(s) Quote: Originally Posted by papaki72 I have a fitness bike with a flat bar and Claris 2x8 shifters and drive train on it. I would like to convert it to a road bike by swapping the handle bar and its shifters with another one that comes with the Shimano Claris 2403 (8x3) on it. Are these compatible, or can they be adjusted so that they can be used with the 2x8 drivetrain? It should shift. The derailleur cable tension and limit screw should be set-up to prevent using the big chainring position of the shifters. There could be some problems if the shifter has trim positions, as it's possible that they won't work as intended. Senior Member Join Date: Sep 2010 Location: Roswell, GA Posts: 8,319 Bikes: '93 Trek 750, '92 Schwinn Crisscross, '93 Mongoose Alta Mentioned: 30 Post(s) Tagged: 0 Thread(s) Quoted: 1438 Post(s) Quote: Originally Posted by Amt0571 It should shift. The derailleur cable tension and limit screw should be set-up to prevent using the big chainring position of the shifters. There could be some problems if the shifter has trim positions, as it's possible that they won't work as intended. I would suggest setting it up to use the big and middle positions of the shifter and letting the cable go slack if accidentally shifted into the small position. Trying to lock out the big ring position with the high limit screw can result in jamming or damage to the shifter if attempting to shift against the stop; having a slack cable will do no damage. Senior Member Join Date: Jun 2020 Location: Maryland Posts: 1,367 Bikes: 1982 Bianchi Sport SX, Rayleigh Tamland 1, Rans V-Rex recumbent, Fuji MTB, 80's Cannondale MTB with BBSHD ebike motor Mentioned: 1 Post(s) Tagged: 0 Thread(s) Quoted: 656 Post(s) I've set up triple shifters to work with just 2 front rings. Should work fine. Senior Member Join Date: Dec 2014 Location: Catalonia Posts: 949 Bikes: Canyon Grand Canyon AL SL 8.0, Triban RC520 Gravel Ltd, Btwin Ultra 520 AF GF, Triban Road 7, Benotto 850 Mentioned: 1 Post(s) Tagged: 0 Thread(s) Quoted: 401 Post(s) Quote: Originally Posted by dsbrantjr I would suggest setting it up to use the big and middle positions of the shifter and letting the cable go slack if accidentally shifted into the small position. Trying to lock out the big ring position with the high limit screw can result in jamming or damage to the shifter if attempting to shift against the stop; having a slack cable will do no damage. It won't damage anything and avoids having 3 clicks and 2 gears. The limit screw would just block the shifter engaging the big chainring. I've ridden for 6 years with a 11sp mountain bike shifter with a 10sp cassette and the last shift blocked with the limit screw without any issue. Senior Member Join Date: Sep 2010 Location: Roswell, GA Posts: 8,319 Bikes: '93 Trek 750, '92 Schwinn Crisscross, '93 Mongoose Alta Mentioned: 30 Post(s) Tagged: 0 Thread(s) Quoted: 1438 Post(s) Quote: Originally Posted by Amt0571 It won't damage anything and avoids having 3 clicks and 2 gears. The limit screw would just block the shifter engaging the big chainring. I've ridden for 6 years with a 11sp mountain bike shifter with a 10sp cassette and the last shift blocked with the limit screw without any issue. If you do manage to get the shifter into that third position, your cable will be very tight and the ratchet under a lot of stress. It may be difficult to shift back down without slacking the cable due to the pressure on the escapement. Senior Member Join Date: Dec 2014 Location: Catalonia Posts: 949 Bikes: Canyon Grand Canyon AL SL 8.0, Triban RC520 Gravel Ltd, Btwin Ultra 520 AF GF, Triban Road 7, Benotto 850 Mentioned: 1 Post(s) Tagged: 0 Thread(s) Quoted: 401 Post(s) Quote: Originally Posted by dsbrantjr If you do manage to get the shifter into that third position, your cable will be very tight and the ratchet under a lot of stress. It may be difficult to shift back down without slacking the cable due to the pressure on the escapement. If you manage to get the shifter into that position I'll suppose you'll have bigger problems. Like a broken shifter paddle, cracked mechanism, broken cable, or at least a slipping cable. Specially on a FD that usually has quite a long throw. As I've said I have run a similar setup on a RD (that needs a lot less travel to engage) for 6 years and I can assure you that it's totally impossible to engage the last position without the cable slipping or breaking something if you set it up correctly. Senior Member Join Date: Jan 2017 Posts: 1,052 Mentioned: 6 Post(s) Tagged: 0 Thread(s) Quoted: 345 Post(s) Likes: 0 Why do you need to replace your 2x shifter? Can't you continue to use it? Is there a problem with mixing your old 2x shifter with the new right side shifter? I thought 3x shifters sometimes don't come with trim? So you'll be losing the ability to trim if you do use it? I switched my Shimano double FD with 11 speed type long pull to a SRAM yaw FD which doesn't need trim, but continued to use the Shimano long pull shifter with trim. I disabled the trim by setting the high limit screw to high trim which effectively disabled high index position. I can easily get the trigger into high index position. I thought that the extra cable pull and tension against the limit screw simply gets taken up by the spring in the parallelogram mechanics. Or maybe I'm wrong and the extra tension is taken by the mechanics in the shifter? Anyway because it's a long pull shifter, both the low index and low trim are slack. Senior Member Join Date: Sep 2012 Location: Brighton, Michigan Posts: 646 Bikes: Optima Baron LR, '14 Nishiki Maricopa,'87 Trek 330 Elance, '89 Miyata 1400, '85 Peugeot PGN10, '04 Fuji Ace, '06 Giant Rincon, '95 Giant Allegre, '83 Trek 620, '86 Schwinn High Sierra Mentioned: 1 Post(s) Tagged: 0 Thread(s) Quoted: 221 Post(s) 2 of my bikes are 3x8 shifters on 2x8 drivetrains. They work great. The front derailleur limit screws keep me from shifting the chain off the outside chainring. Senior Member Join Date: Feb 2015 Location: Mission Viejo Posts: 5,577 Bikes: 1986 Cannondale SR400 (Flat bar commuter), 1988 Cannondale Criterium XTR, 1992 Serotta T-Max, 1995 Trek 970 |
