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I am wondering if you put on a suspension fork if it would raise the bottom brackets up enough to do some more serious off roading? I put a fox 36 cut down to 140MM of travel on our KHS tandemaniam bike that has a rated BB height of 11.2 inches which is almost identical to the Cannondale. With it we get plenty of clearance and it still handles great. You will slack out the front end but the Fox 35 is designed to work with a slack front end.
 

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MTB Tandem Nut
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I am wondering if you put on a suspension fork if it would raise the bottom brackets up enough to do some more serious off roading? I put a fox 36 cut down to 140MM of travel on our KHS tandemaniam bike that has a rated BB height of 11.2 inches which is almost identical to the Cannondale. With it we get plenty of clearance and it still handles great. You will slack out the front end but the Fox 35 is designed to work with a slack front end.
We just finished doing such a "conversion" on the '14 T29 by adding a WB Loop Tandem and a suspension post on the rear. The front BB is raised some, but sagged height will be similar to stock, maybe 1.5cm higher. Rear also raised up some, but not sure if it's enough or not.
The one we did was shipped out immediately after test-ride (not on dirt), so I don't know how well it will do off-road with the fork on it. We'll put another one together to keep here at the shop, and then maybe get a better feel for off-road capability.
The test ride around the shop street showed that the front definitely got a little slacker, but didn't feel overly floppy. Again, won't know for sure until we get one dirty. BTW, cost of adding the fork/seatpost and required headset and stem puts the total cost of the tandem back around original MSRP of $2,739 + -.
 

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We just finished doing such a "conversion" on the '14 T29 by adding a WB Loop Tandem and a suspension post on the rear. The front BB is raised some, but sagged height will be similar to stock, maybe 1.5cm higher. Rear also raised up some, but not sure if it's enough or not.
The one we did was shipped out immediately after test-ride (not on dirt), so I don't know how well it will do off-road with the fork on it. We'll put another one together to keep here at the shop, and then maybe get a better feel for off-road capability.
The test ride around the shop street showed that the front definitely got a little slacker, but didn't feel overly floppy. Again, won't know for sure until we get one dirty. BTW, cost of adding the fork/seatpost and required headset and stem puts the total cost of the tandem back around original MSRP of $2,739 + -.
Did the original fork come as suspension corrected? You could put on a fox 34 with 15mm through axle to raise it up more and that fork is designed for a slacker head angle. Probably OK for a light team.
I am starting to think a tandem with 26 inch wheels will be stronger and the choice for beefy forks much better.
 

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MTB Tandem Nut
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The original fork is said to be suspension-corrected in Cannondale's product literature, and from just visually comparing it with the WB Loop, it would look to be close. The conversion headset from Cannondale comes with two options for the lower cup, an internal one like the one on the stock T29 and an external one that raises everything about 15-20mm. After the initial test run, I elected to keep the internal lower race, as the front end was starting to feel slack. The external lower race would provide better clearance for the WB Loop lower crown/frame interaction, but I attached a rubber bumper there instead. We'll have to get some trail time on one, and hopefully some riders here will provide feedback, but I think if the fork is as short as the DC Loop is, it probably is not detrimental to the handling. Single-crown forks tend to have longer C-A measurements for the same travel, so not sure what a Fox would do.
26" does provide stronger wheels and more fork choice, but for hardtail, I think 29" is was better as a platform; definitely smoother off-road.
 

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The original fork is said to be suspension-corrected in Cannondale's product literature, and from just visually comparing it with the WB Loop, it would look to be close. The conversion headset from Cannondale comes with two options for the lower cup, an internal one like the one on the stock T29 and an external one that raises everything about 15-20mm. After the initial test run, I elected to keep the internal lower race, as the front end was starting to feel slack. The external lower race would provide better clearance for the WB Loop lower crown/frame interaction, but I attached a rubber bumper there instead. We'll have to get some trail time on one, and hopefully some riders here will provide feedback, but I think if the fork is as short as the DC Loop is, it probably is not detrimental to the handling. Single-crown forks tend to have longer C-A measurements for the same travel, so not sure what a Fox would do.
26" does provide stronger wheels and more fork choice, but for hardtail, I think 29" is was better as a platform; definitely smoother off-road.
I am having good luck with my old KHS tandem with the Fox 36 reduced to 140MM travel.
Took the head angle from 74 degrees to about 69 degrees without any sag. But I think the Fox 36 is designed around a slack head angle.
Not sure of the bottom bracket height on the KHS but will measure it soon. I think the handling is just fine. Like any bike you will eventually figure it out unless things are way too wonky. It is like riding a tandem without a partner, it feels real strange at first,but after a while you get use to it.
It seems to me the 100mm loop fork might make things worse once you get sag and suspension travel factored in with regards to BB height.
 

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MTB Tandem Nut
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I am having good luck with my old KHS tandem with the Fox 36 reduced to 140MM travel.
Took the head angle from 74 degrees to about 69 degrees without any sag. But I think the Fox 36 is designed around a slack head angle.
Not sure of the bottom bracket height on the KHS but will measure it soon. I think the handling is just fine. Like any bike you will eventually figure it out unless things are way too wonky. It is like riding a tandem without a partner, it feels real strange at first,but after a while you get use to it.
It seems to me the 100mm loop fork might make things worse once you get sag and suspension travel factored in with regards to BB height.
Nope - the fork sagged is just a bit longer than the rigid OE fork. By "making things worse", I assume you mean too steep? I don't think that will be a problem with these tandems as they're currently designed. 69 degrees would seem to flop around a lot on slow climbs and in some of the twisty stuff we have here, but if it works for you, that's what matters. After all, everyone has their own preferences on what works. The non-loaded BB height is higher with the fork installed, and the loaded bb height is slightly higher, so only under full compression would the bb height be significantly lower.
 

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MTB Tandem Nut
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Alex, any thoughts on a Lefty Supermax as a tandem fork?
After seeing the Lefty Max on a Calfee, I had a series of emails with the engineers at Cannondale - their take is: "Absolutely not tandem approved". Don't know if that's due to potential liability in the event of a failure due to not testing it under tandem loads, or if there is a design factor that precludes it being a good choice. Naturally, they didn't go into much detail after stating their position.
 

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Nope - the fork sagged is just a bit longer than the rigid OE fork. By "making things worse", I assume you mean too steep? I don't think that will be a problem with these tandems as they're currently designed. 69 degrees would seem to flop around a lot on slow climbs and in some of the twisty stuff we have here, but if it works for you, that's what matters. After all, everyone has their own preferences on what works. The non-loaded BB height is higher with the fork installed, and the loaded bb height is slightly higher, so only under full compression would the bb height be significantly lower.
By worse I meant in regards to lowering the BB even more.
We have plenty of long slow climbs here. As far as not being able to make a turn we are more constrained by the length of the bike than the handling. The long travel fork sure makes it a lot more off-road capable and fun. In a lot of ways the front end feels more stable and capable than my single hard tail but I am reluctant to push it too hard since a recovery for a miscue is harder to make.
I guess that is why there are so many choices in products. What works for some may not work for others
 

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Sisu did you try the lefty? Any pictures? Which one max, supermax....? Thoughts? We are torn between a fat bike tandem a Cannondale 29er or other 29er. We have always ridden a road tandem but as mentioned above between cell phones, texting, music and on and on the roads just aren't what they use to be...so we are looking to try the beach and off road paths. Suggestions are always appreciated...thank you
 

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Suggestions are always appreciated...thank you
Depends on what you're going to do with the tandem. If dry sand beach riding is your think, fat is the only way to go. If beach riding is minor compared to dirt riding and is more wet sand beach than dry anyway, Fandango or ECdM (with the difference there depending on what your dirt riding consists of) would be my suggestion.

So, tell us more about what you guys are going to do with the bike.
 

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Okay thoughts not sure yet done so much road riding the trail and beaches are all new to us. We tandemed Mt Washington humbling but enjoy climbing done road rides 50-75 miles a day enjoyed them. Can't see us doing the real off road technical stuff just loose dirt trails and the beach thing since we are close to the beaches. Heard there are some nice trails and rail trails over in Maryland and up in Pennsylvania.....so putting our toes in the water and know we can't do anything other than road with ours. Rode the new Java with 2" tires and loved the stability and thought the fat tire would give a decent ride, stability and traction in almost any condition....thank you
 

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Discussion Starter #76
I didn't end up putting a Lefty Supermax on our Cdale 29er--Cdale tech folks said it wasn't tandem rated, and the low bb of this bike makes better suited to gravel roads. It's a good bike for that application.
 

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Discussion Starter #80
Check with CDale dealers to see if they have any leftover '14 tandems. I found mine in MI.
 
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