Installing Gates belt system - any tips or tricks?
01-13-24, 03:33 PM
#1
Full Member
Thread Starter
Join Date: Feb 2010
Posts: 228
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
Installing Gates belt system - any tips or tricks?
Picked up a Gates kit to install on my Cannondale T2 from Precision Tandems. Bike currently has FSA Gossamer cranks and a Shimano 105 drivetrain.
Seems relatively straightforward, just have to find the time to get it done. Been awhile since I tinkered with an eccentric BB, so might post some questions here for wisdom when I get to it. And the PT folks were gracious in saying to reach out if questions as well.
If any fellow members here have done this in the past, I'd appreciate any tips or things to look out for.
Thanks.
Seems relatively straightforward, just have to find the time to get it done. Been awhile since I tinkered with an eccentric BB, so might post some questions here for wisdom when I get to it. And the PT folks were gracious in saying to reach out if questions as well.
If any fellow members here have done this in the past, I'd appreciate any tips or things to look out for.
Thanks.
01-13-24, 08:00 PM
#2
Junior Member
I did the same thing on both my T2 (same bike with the same components as yours) and a Cannondale 29er Tandem. Awesome upgrade on both bikes!
Most important thing is to make sure that your timing chainrings are PERFECTLY aligned. This may be tricker that it seems, due to imperfections with the construction of the frame--the BB shells may not be precisely 90 degrees from the boom tube. Use an aluminum straight edge against the new pulleys, and then add spacers as necessary. Also, due to where Cannondale installed the bottom bracket spacers, you may or may not need to move them around (I ended up with a spacer on each side of the BB, per spec, but the bike came with two spacers on the same side on the pilots BB). Due to less-than-perfect machining of the Gossamer's spiders, you may also need to add very thin shims to keep the pulleys "flat." It took be several tries to get everything aligned correctly and the pulleys flat. Obviously, your mileage may vary depending on how well machined the spiders are, and how well built your frame is. Could be a piece of cake, or several frustrating tweaks.
Last, but not least, I don't think that the belt tension needs to be as high as Gates suggests. The T2 frame is very stiff, so you're unlikely to need to apply enough tension to take up muck slack from frame flex. I have found that tension changes a lot with temperature, since the frame will expand and contract on warmer and cooler days. I generally try to tension it on an "average" day, and then tweak it if necessary when the seasons change. I MUCH prefer the Gates Cricket tool over the iPhone app for measuring chain tension.
OK, one more thing: Belts don't stretch at all--so you may forget to service your eccentric frequently enough--which can lead to it freezing up. Always clean and lube it at least once a year, or more if you ride in the wet often or wash your bike frequently.
Most important thing is to make sure that your timing chainrings are PERFECTLY aligned. This may be tricker that it seems, due to imperfections with the construction of the frame--the BB shells may not be precisely 90 degrees from the boom tube. Use an aluminum straight edge against the new pulleys, and then add spacers as necessary. Also, due to where Cannondale installed the bottom bracket spacers, you may or may not need to move them around (I ended up with a spacer on each side of the BB, per spec, but the bike came with two spacers on the same side on the pilots BB). Due to less-than-perfect machining of the Gossamer's spiders, you may also need to add very thin shims to keep the pulleys "flat." It took be several tries to get everything aligned correctly and the pulleys flat. Obviously, your mileage may vary depending on how well machined the spiders are, and how well built your frame is. Could be a piece of cake, or several frustrating tweaks.
Last, but not least, I don't think that the belt tension needs to be as high as Gates suggests. The T2 frame is very stiff, so you're unlikely to need to apply enough tension to take up muck slack from frame flex. I have found that tension changes a lot with temperature, since the frame will expand and contract on warmer and cooler days. I generally try to tension it on an "average" day, and then tweak it if necessary when the seasons change. I MUCH prefer the Gates Cricket tool over the iPhone app for measuring chain tension.
OK, one more thing: Belts don't stretch at all--so you may forget to service your eccentric frequently enough--which can lead to it freezing up. Always clean and lube it at least once a year, or more if you ride in the wet often or wash your bike frequently.
01-14-24, 06:53 AM
#3
Full Member
Thread Starter
Join Date: Feb 2010
Posts: 228
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
thanks!
I did the same thing on both my T2 (same bike with the same components as yours) and a Cannondale 29er Tandem. Awesome upgrade on both bikes!
Most important thing is to make sure that your timing chainrings are PERFECTLY aligned. This may be tricker that it seems, due to imperfections with the construction of the frame--the BB shells may not be precisely 90 degrees from the boom tube. Use an aluminum straight edge against the new pulleys, and then add spacers as necessary. Also, due to where Cannondale installed the bottom bracket spacers, you may or may not need to move them around (I ended up with a spacer on each side of the BB, per spec, but the bike came with two spacers on the same side on the pilots BB). Due to less-than-perfect machining of the Gossamer's spiders, you may also need to add very thin shims to keep the pulleys "flat." It took be several tries to get everything aligned correctly and the pulleys flat. Obviously, your mileage may vary depending on how well machined the spiders are, and how well built your frame is. Could be a piece of cake, or several frustrating tweaks.
Last, but not least, I don't think that the belt tension needs to be as high as Gates suggests. The T2 frame is very stiff, so you're unlikely to need to apply enough tension to take up muck slack from frame flex. I have found that tension changes a lot with temperature, since the frame will expand and contract on warmer and cooler days. I generally try to tension it on an "average" day, and then tweak it if necessary when the seasons change. I MUCH prefer the Gates Cricket tool over the iPhone app for measuring chain tension.
OK, one more thing: Belts don't stretch at all--so you may forget to service your eccentric frequently enough--which can lead to it freezing up. Always clean and lube it at least once a year, or more if you ride in the wet often or wash your bike frequently.
Most important thing is to make sure that your timing chainrings are PERFECTLY aligned. This may be tricker that it seems, due to imperfections with the construction of the frame--the BB shells may not be precisely 90 degrees from the boom tube. Use an aluminum straight edge against the new pulleys, and then add spacers as necessary. Also, due to where Cannondale installed the bottom bracket spacers, you may or may not need to move them around (I ended up with a spacer on each side of the BB, per spec, but the bike came with two spacers on the same side on the pilots BB). Due to less-than-perfect machining of the Gossamer's spiders, you may also need to add very thin shims to keep the pulleys "flat." It took be several tries to get everything aligned correctly and the pulleys flat. Obviously, your mileage may vary depending on how well machined the spiders are, and how well built your frame is. Could be a piece of cake, or several frustrating tweaks.
Last, but not least, I don't think that the belt tension needs to be as high as Gates suggests. The T2 frame is very stiff, so you're unlikely to need to apply enough tension to take up muck slack from frame flex. I have found that tension changes a lot with temperature, since the frame will expand and contract on warmer and cooler days. I generally try to tension it on an "average" day, and then tweak it if necessary when the seasons change. I MUCH prefer the Gates Cricket tool over the iPhone app for measuring chain tension.
OK, one more thing: Belts don't stretch at all--so you may forget to service your eccentric frequently enough--which can lead to it freezing up. Always clean and lube it at least once a year, or more if you ride in the wet often or wash your bike frequently.
01-17-24, 10:54 AM
#4
Full Member
If you haven’t seen it already, check out this thread where I solved an issue where our bike with gossamer cranks and a gates belt was eating bottom brackets.
https://www.bikeforums.net/tandem-cy...-brackets.html
i went down the rabbit hole using the dial indicators, however, I would recommend using the gates clicker gauge tool (sorry, I can’t recal the tools name, it should be in the thread). I agree that the belt does not need to be as tight as gates recommends and running it a little looser will save your bottom brackets,
https://www.bikeforums.net/tandem-cy...-brackets.html
i went down the rabbit hole using the dial indicators, however, I would recommend using the gates clicker gauge tool (sorry, I can’t recal the tools name, it should be in the thread). I agree that the belt does not need to be as tight as gates recommends and running it a little looser will save your bottom brackets,
01-17-24, 09:01 PM
#5
pan y agua
Join Date: Aug 2005
Location: Jacksonville
Posts: 31,304
Bikes: Willier Zero 7; Merlin Extralight; Calfee Dragonfly tandem, Calfee Adventure tandem; Cervelo P2; Motebecane Ti Fly 29er; Motebecanne Phantom Cross; Schwinn Paramount Track bike
Mentioned: 17 Post(s)
Tagged: 0 Thread(s)
Quoted: 1447 Post(s)
Liked 728 Times
in
373 Posts
Plus one on the belt does not need to be as tight as Gate specs. As long as it doesn’t skip; it’s tight enough.
Would also add, Do not the roll the belt on like you would do a chain. While the belt is very strong, they will break if you twist them
Would also add, Do not the roll the belt on like you would do a chain. While the belt is very strong, they will break if you twist them
__________________
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.
Likes For merlinextraligh:
01-18-24, 01:52 PM
#6
Junior Member
Another T2 team here, though ours came with the belt drive. Concur with both of Toby's points.
We hit 10K miles last year and are on our third set of BB30 bearings - when we got the bike the LBS had cranked the tension up way too high.
Definitely release the belt tension and service both BBs yearly. The eccentric loves to freeze up. Also be sure to follow the removal procedure to the letter, it's easy to put an allen wrench on the wrong bolt when disassembling.
Definitely release the belt tension and service both BBs yearly. The eccentric loves to freeze up. Also be sure to follow the removal procedure to the letter, it's easy to put an allen wrench on the wrong bolt when disassembling.
Likes For Yamato72:
01-19-24, 10:39 AM
#7
Newbie
Make sure to loosen off the belt side chain ring bolts at the tightest belt tension, then retighten to equalise the tension in the belt. This is the same for a chain drive, https://www.sheldonbrown.com/synchain.html I mark the belts direction of rotation as it tracks better.
Likes For mikemelbrooks:
01-19-24, 11:48 AM
#8
Junior Member
Make sure to loosen off the belt side chain ring bolts at the tightest belt tension, then retighten to equalise the tension in the belt. This is the same for a chain drive, https://www.sheldonbrown.com/synchain.html I mark the belts direction of rotation as it tracks better.
