Adding disc brake idiots guide wanted
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Adding disc brake idiots guide wanted
I want to add a rear disc brake in addition to the caliper brakes on the new-to-us recumbent tandem. The bike is used for touring so is usually fairly highly loaded.
I originally thought I would just throw money at the problem and have a bike shop take care of it, but every shop that I called in a 50 mile radius blew me off like a bad smell. Apparently the words recumbent and tandem used together inspire fear and loathing.
I would have thought that youtube would have been resplendent with videos discussing how to do this but the few I have been able to find that are even close to the subject leave something to be desired. And so I turn to the forum.
My plan is to replace the hub in my current wheel and then use one of the myriad of adapter kits. The rear forks are 140 mm so lots of room. I am a long way from a bike mechanic but I do have a reasonable collection of tools and I am willing to buy more should that be required.
The questions:
Can someone recommend a link that would cover this topic?
Recommendations for a specific hub and adapter. I would like something that will take a lot of abuse but it doesn't have to be super light or made from unicorn eyelashes.
I have considered going with an internally geared hub but I don't really know anything about them. Would they stand up to the abuse inherent in touring? Any recommendations for these?
Has anyone put a "fiber chain" or belt on their bike? If I could find one long enough would this be a good idea?
I did search the forum for information but didn't find anything, so if this has been covered before I apologize.
Thank you for your thoughts and advice.
K.
I originally thought I would just throw money at the problem and have a bike shop take care of it, but every shop that I called in a 50 mile radius blew me off like a bad smell. Apparently the words recumbent and tandem used together inspire fear and loathing.
I would have thought that youtube would have been resplendent with videos discussing how to do this but the few I have been able to find that are even close to the subject leave something to be desired. And so I turn to the forum.
My plan is to replace the hub in my current wheel and then use one of the myriad of adapter kits. The rear forks are 140 mm so lots of room. I am a long way from a bike mechanic but I do have a reasonable collection of tools and I am willing to buy more should that be required.
The questions:
Can someone recommend a link that would cover this topic?
Recommendations for a specific hub and adapter. I would like something that will take a lot of abuse but it doesn't have to be super light or made from unicorn eyelashes.
I have considered going with an internally geared hub but I don't really know anything about them. Would they stand up to the abuse inherent in touring? Any recommendations for these?
Has anyone put a "fiber chain" or belt on their bike? If I could find one long enough would this be a good idea?
I did search the forum for information but didn't find anything, so if this has been covered before I apologize.
Thank you for your thoughts and advice.
K.
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Probably wasn't the words recumbent or tandem. I'd think most bike shops would shy away from anything that isn't just remove and replace. Even for a normal bike.
What you are asking for is essentially experimental. And they won't recover monetarily the time they spend on the project. And during that time spent, they likely would loose several times as much revenue from just normal bike maintenance things that come along.
What you have to do is find someone that views your project with the same passion for the challenge of making it all fit and work well. And is willing to volunteer for friendship and maybe a case of scotch or beer.
What you are asking for is essentially experimental. And they won't recover monetarily the time they spend on the project. And during that time spent, they likely would loose several times as much revenue from just normal bike maintenance things that come along.
What you have to do is find someone that views your project with the same passion for the challenge of making it all fit and work well. And is willing to volunteer for friendship and maybe a case of scotch or beer.
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Can someone recommend a link that would cover this topic? I can't, but I have no surprise that there would be so few recumbent tandem disk brake install vids out there given the few of these bikes out there
Recommendations for a specific hub and adapter. I like Phil Wood hubs and don't know which of the various adapters you are talking about. Caliper to pre existing frame mount? No frame mount adapter that works off the axle and the canti boss? I would like something that will take a lot of abuse but it doesn't have to be super light or made from unicorn eyelashes. Sorry but this type of question has always made me question the understandings or expectations of the questioner? I don't want to spend much $, will abuse the product and expect it to last because it's not lightweight...
I have considered going with an internally geared hub but I don't really know anything about them. Would they stand up to the abuse inherent in touring? Many IGHs have both low gearing limitations and most are not rated for tandem use. And none want to be abused. Any recommendations for these? None that I know of
Has anyone put a "fiber chain" or belt on their bike? Yes, many have. If I could find one long enough would this be a good idea? Perhaps but that depends on both your goals and willingness to deal with the drawbacks of a belt drive. The only tandems that I have seen/serviced with belts used them for the timing "chain", not for the final drive to the rear wheel. Andy
Recommendations for a specific hub and adapter. I like Phil Wood hubs and don't know which of the various adapters you are talking about. Caliper to pre existing frame mount? No frame mount adapter that works off the axle and the canti boss? I would like something that will take a lot of abuse but it doesn't have to be super light or made from unicorn eyelashes. Sorry but this type of question has always made me question the understandings or expectations of the questioner? I don't want to spend much $, will abuse the product and expect it to last because it's not lightweight...
I have considered going with an internally geared hub but I don't really know anything about them. Would they stand up to the abuse inherent in touring? Many IGHs have both low gearing limitations and most are not rated for tandem use. And none want to be abused. Any recommendations for these? None that I know of
Has anyone put a "fiber chain" or belt on their bike? Yes, many have. If I could find one long enough would this be a good idea? Perhaps but that depends on both your goals and willingness to deal with the drawbacks of a belt drive. The only tandems that I have seen/serviced with belts used them for the timing "chain", not for the final drive to the rear wheel. Andy
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Those disc brake adapter kits are nearly universally considered at least a bad idea, if not outright dangerous.
I think that most IGHs are not meant for tandem use. They have torque input limits, which makes them less suitable for tandems. Rohloffs are approved for tandem use, but they are extremely expensive compared to Shimano IGHs.
In order to fit a Gates belt drive to a bike, you need to have a break in the chainstay or seatstay for the belt to fit through. If your frame isn't equipped with one you can't put a continuous belt on. There are split belts, but I don't have experience with them. You also need to be able to tension the belt, e.g. with an eccentric bottom bracket or sliding dropouts. I don't know how long your recumbent chain is, but I think they are mostly longer than belts are available for. Belts generally should be bent backwards, which would also disqualify their use on many recumbents.
I think that most IGHs are not meant for tandem use. They have torque input limits, which makes them less suitable for tandems. Rohloffs are approved for tandem use, but they are extremely expensive compared to Shimano IGHs.
In order to fit a Gates belt drive to a bike, you need to have a break in the chainstay or seatstay for the belt to fit through. If your frame isn't equipped with one you can't put a continuous belt on. There are split belts, but I don't have experience with them. You also need to be able to tension the belt, e.g. with an eccentric bottom bracket or sliding dropouts. I don't know how long your recumbent chain is, but I think they are mostly longer than belts are available for. Belts generally should be bent backwards, which would also disqualify their use on many recumbents.
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Probably wasn't the words recumbent or tandem. I'd think most bike shops would shy away from anything that isn't just remove and replace. Even for a normal bike.
What you are asking for is essentially experimental. And they won't recover monetarily the time they spend on the project. And during that time spent, they likely would loose several times as much revenue from just normal bike maintenance things that come along.
What you have to do is find someone that views your project with the same passion and is willing to volunteer for friendship and maybe a case of scotch or beer.
What you are asking for is essentially experimental. And they won't recover monetarily the time they spend on the project. And during that time spent, they likely would loose several times as much revenue from just normal bike maintenance things that come along.
What you have to do is find someone that views your project with the same passion and is willing to volunteer for friendship and maybe a case of scotch or beer.
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I want to add a rear disc brake in addition to the caliper brakes on the new-to-us recumbent tandem.
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Plus the size, no way could we accommodate something that size unless if was work on while customer waits and leaves with it. It would also probably take up 2 bays while being worked on.
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It could be a lot of factors involved in a shop not wanting to work on the project. Space is a huge factor and being able to mount it to a stand easily and safely is another. Most shops do not have the ability to deal with recumbents much less a tandem recumbent and maybe they would work on it if they could but it is a lot more work. Plus adding odd mounts for things that do not exist on the bike and are safety related is not something any shop is going to touch unless they are frame builders and are welding something on. A recumbent shop probably has a stand for a recumbent and could work on it but then again they probably don't want liability in installing some jenky add on disc brake kit (and I am not talking specifics I am just talking in general) I know I wouldn't have any of my techs install something like that no matter what money was involved as the risk is too high. Just because someone does sell something doesn't mean you should buy it.
I would post pictures and info on the bike so we know what we are dealing with and can make recommendations for brakes that are going to be safer.
In terms of IGHs they are great but Rohloff might be your only bet and even that is not something I would really want on a tandem personally (though I do love Rohloff) I think the added stress for touring would be closer to the limits on that hub. I would stick with a good high quality derailleur system. Shimano XT would be my top choice but if you wanted road components 105 or Ultegra would be a fine choice or GRX in the 11 or 12 speed spec.
Gates Carbon Drives are excellent but do require either a gearbox (Pinion) or an IGH or to be run as a single speed. For tandems they are typically used for timing but unsure if that would work here but if so I would recommend it for timing it does cut out weight and maintenance and costs less over the long term generally especially on a higher used item.
I would post pictures and info on the bike so we know what we are dealing with and can make recommendations for brakes that are going to be safer.
In terms of IGHs they are great but Rohloff might be your only bet and even that is not something I would really want on a tandem personally (though I do love Rohloff) I think the added stress for touring would be closer to the limits on that hub. I would stick with a good high quality derailleur system. Shimano XT would be my top choice but if you wanted road components 105 or Ultegra would be a fine choice or GRX in the 11 or 12 speed spec.
Gates Carbon Drives are excellent but do require either a gearbox (Pinion) or an IGH or to be run as a single speed. For tandems they are typically used for timing but unsure if that would work here but if so I would recommend it for timing it does cut out weight and maintenance and costs less over the long term generally especially on a higher used item.
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Does the bike currently use a caliper brake in the rear, or does it have canti/v brake mounts? What material is the frame? I wouldn’t trust any of the “bolt-on” disc brake adapters personally. I’d look into having a proper brake mount welded to the frame by a competent frame builder, which would be $$$ but the safe way to go about adding a disc brake.
As a shop mechanic, recumbent tandems inspire no fear, but I won’t help install sketchy brake setups.
As a shop mechanic, recumbent tandems inspire no fear, but I won’t help install sketchy brake setups.
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Post a picture of this bike. If your recumbent uses a conventional fork, the easiest course of action would be to change out the fork to one with disk brake mounts.
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You're asking a shop to perform an experiment and stand by it if it fails. First, you have to figure out how to attach a mount so it doesn't move when you bump it. Second, it has to be stiff enough so it doesn't deflect when you actuate the brake. Third, the fork is not designed to handle braking force from the hub. It will deflect, chatter, and/or oscillate.
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first question....how much have you ridden the new bike? is there really a problem with braking power?
over all you would be better of throwing money at a new bike than trying to do things like add disc brakes or belt drive to a bike not designed for them
over all you would be better of throwing money at a new bike than trying to do things like add disc brakes or belt drive to a bike not designed for them
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Thank you everyone for your input. It is truly much appreciated.
To be clear. I am in no way faulting the bike shops for blowing me off. Some could have done so a bit more nicely, but most were pretty straight forward and said they had never done anything like it and didn't want to try. I would much sooner have someone tell me to go away rather than do a poor job that has the potential to land me in a ditch. I recognize that shops have to make money to keep the lights on, send their kids to college etc.
I am also not trying to do this on the cheap. I was in communication with a bike shop in California to build a tandem and it was the lead time, 2 to 3 years, not the price that was the problem. When I said that I didn't need it to be made out of unicorn eyelashes I was referring to the super light, exotic racing equipment. We are an old couple who frequently stop and smell the locally brewed beers. If something weighs 2 grams more and will last twice as long I am all in even if it is twice as expensive. This is likely to be our last bike so we are okay with spending money on the components.
We wore out our old linear tandem and gave it to a couple we met in Portugal. It had both caliper and drum brakes which allowed the stoker to also have some braking control. This is the main reason for wanting to add another brake.
The bike is a double vision which as I understand it means it is more than twenty years old. The forks are definitely not standard and are integral to the frame.
Apparently I was also incorrect with regard to the existing brakes. They are Magura classics which seem to have a love them or hate them following.
Replacing the timing chain with a fiber belt would be a nice addition. On of the problems associated with our previous tandem was the great mass of chain flailing about, collecting dirt and transferring it to the riders.
To be clear. I am in no way faulting the bike shops for blowing me off. Some could have done so a bit more nicely, but most were pretty straight forward and said they had never done anything like it and didn't want to try. I would much sooner have someone tell me to go away rather than do a poor job that has the potential to land me in a ditch. I recognize that shops have to make money to keep the lights on, send their kids to college etc.
I am also not trying to do this on the cheap. I was in communication with a bike shop in California to build a tandem and it was the lead time, 2 to 3 years, not the price that was the problem. When I said that I didn't need it to be made out of unicorn eyelashes I was referring to the super light, exotic racing equipment. We are an old couple who frequently stop and smell the locally brewed beers. If something weighs 2 grams more and will last twice as long I am all in even if it is twice as expensive. This is likely to be our last bike so we are okay with spending money on the components.
We wore out our old linear tandem and gave it to a couple we met in Portugal. It had both caliper and drum brakes which allowed the stoker to also have some braking control. This is the main reason for wanting to add another brake.
The bike is a double vision which as I understand it means it is more than twenty years old. The forks are definitely not standard and are integral to the frame.
Apparently I was also incorrect with regard to the existing brakes. They are Magura classics which seem to have a love them or hate them following.
Replacing the timing chain with a fiber belt would be a nice addition. On of the problems associated with our previous tandem was the great mass of chain flailing about, collecting dirt and transferring it to the riders.
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A pic is worth a thousand words.
That hub is meant to have an Arai Drum brake installed. They are only available on the used market in their unmolested original form. From what I remember Tandems East (?) may have some reconditioned units available. But the cooling fins have been machined off sort of defeating the purpose of the unit.
I have an original unit I bought used but never put in to service. PM if interested.
FWIW: I know of no reason a Phil hub could/should ever need replacement. New bearings press in/press out with a minimal of shop time. Even then, Phil bearings are not known for short lifespans. You'll probably have that hub in a few more rims before that time is due.
That hub is meant to have an Arai Drum brake installed. They are only available on the used market in their unmolested original form. From what I remember Tandems East (?) may have some reconditioned units available. But the cooling fins have been machined off sort of defeating the purpose of the unit.
I have an original unit I bought used but never put in to service. PM if interested.
FWIW: I know of no reason a Phil hub could/should ever need replacement. New bearings press in/press out with a minimal of shop time. Even then, Phil bearings are not known for short lifespans. You'll probably have that hub in a few more rims before that time is due.
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Wait...what? Am I missing something here?
A frame has to be designed to accept a belt drive (needs a drive-side seatstay that comes apart) and disc brakes. Your frame apparently isn't designed for those components. That's why bike shops are turning you down.
A frame has to be designed to accept a belt drive (needs a drive-side seatstay that comes apart) and disc brakes. Your frame apparently isn't designed for those components. That's why bike shops are turning you down.
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Thank you everyone for your input.
The bike is a double vision which as I understand it means it is more than twenty years old. The forks are definitely not standard and are integral to the frame.
Apparently I was also incorrect with regard to the existing brakes. They are Magura classics which seem to have a love them or hate
The bike is a double vision which as I understand it means it is more than twenty years old. The forks are definitely not standard and are integral to the frame.
Apparently I was also incorrect with regard to the existing brakes. They are Magura classics which seem to have a love them or hate
You have Magura hydraulic caliper brakes. As you noted, some people love them, some people hate them.
The rear hub is set up for an Arai drum “drag” brake. This requires no additional fittings on the frame but isn’t a “stopping” brake. Many times it’s controlled by a friction shifter, sometimes by the stoker. I’m not sure if the Arai brake is still being made- maybe Tandems East knows.
If you have your heart set on disk brakes, contact an experienced frame builder. Add-on mounts were a thing in the infancy of disk brakes but I haven’t seen anything like that for 15 or 20 years.
Jeff (whose recumbent bike experience predates index shifting)
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The Double Vision tandem is a monotube like the other Vision recumbents. It’s one really long, large diameter tube. Adapting a belt to the timing side could be straightforward if the correct rings and belt exist.
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And I'm sticking with my response about the disc brake. You can't just add one to a frame that hasn't been designed for it.
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Now as to whether or not an $1800 Rohloff hub (the only tandem rated hub I know of) and modifying the frame spacing to accommodate it's 135mm disc spacings within the OP's budget is a different matter. *Thinking out loud*Tig in a 2.5 (or 5mm) washer on the inboard side of each dropout & use an extra long skewer?
But yeah, disc tabs are probably left to a frame builder who knows what he's doing. Definitely not worth the trouble.
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If you study the picture, it appears that at the dropout there is a bolt that joins the top of the drop out to the seat stay. There is no substitute for seeing the thing in person in real life, but it appears that it would allow for a belt.
Now as to whether or not an $1800 Rohloff hub (the only tandem rated hub I know of) and modifying the frame spacing to accommodate it's 135mm disc spacings within the OP's budget is a different matter. *Thinking out loud*Tig in a 2.5 (or 5mm) washer on the inboard side of each dropout & use an extra long skewer?
But yeah, disc tabs are probably left to a frame builder who knows what he's doing. Definitely not worth the trouble.
Now as to whether or not an $1800 Rohloff hub (the only tandem rated hub I know of) and modifying the frame spacing to accommodate it's 135mm disc spacings within the OP's budget is a different matter. *Thinking out loud*Tig in a 2.5 (or 5mm) washer on the inboard side of each dropout & use an extra long skewer?
But yeah, disc tabs are probably left to a frame builder who knows what he's doing. Definitely not worth the trouble.
Regarding the disc brake, though -- my understanding is that it's more than just adding the mounts. The stays (or fork legs for a front brake) must be strong enough to withstand the forces applied to them by hard braking. That's difficult (uneconomical) to add to a frame.
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Finding an Arai drum brake is going to be a little tougher but probably do-able. However the Magura Rim brakes are decent brakes and new HS33s (which are the best of them currently though you can get 22s and 11s) as well as aftermarket pads from KoolStop can easily be found and with good rims you will have excellent stopping power
I really wouldn't try for any disc brakes unless you find a frame builder willing to take on the project. However a new front fork should be something you could find I don't know the specs of it but it looks like this website might be of some help:Vision Recumbent Bicycles: Guide to bicycle models and versions
I really wouldn't try for any disc brakes unless you find a frame builder willing to take on the project. However a new front fork should be something you could find I don't know the specs of it but it looks like this website might be of some help:Vision Recumbent Bicycles: Guide to bicycle models and versions
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OP,
You might have better luck asking on and searching the Tandem forum, and perhaps a Tandem-specific shop.
My Trek T1000 has a disc-mount adapter support as well as the pacman tab for drum brake. I started down the path of adding a disc brake rear, intended as a drag break and not to replace rim brakes, which IIUC your later post made clear is what you're hoping to do.
I should tell you that multiple experienced tandem posters chimed in to say that a disc, even large, was NOT a drag brake substitute for descending on a loaded tandem and avoiding brake fade. Some teams reported no problem, if course, but hills and weights and speeds are not likely to be the same. And it's certainly a separate place to be scrubbing heat, so would have to be better than rim-only.... Lots of uncertainty that probably reinforces why a shop was hesitant.
Forum consensus seemed to be that the T1000's disc support existed for those wanting to swap out rim brakes for discs. I never found a Trek-source discussing it.
There are/were threaded adapters to bolt a disc-mount to the hub. I'd be hesitant to do that if the frame wasn't built for that load on the frame member.
You might have better luck asking on and searching the Tandem forum, and perhaps a Tandem-specific shop.
My Trek T1000 has a disc-mount adapter support as well as the pacman tab for drum brake. I started down the path of adding a disc brake rear, intended as a drag break and not to replace rim brakes, which IIUC your later post made clear is what you're hoping to do.
I should tell you that multiple experienced tandem posters chimed in to say that a disc, even large, was NOT a drag brake substitute for descending on a loaded tandem and avoiding brake fade. Some teams reported no problem, if course, but hills and weights and speeds are not likely to be the same. And it's certainly a separate place to be scrubbing heat, so would have to be better than rim-only.... Lots of uncertainty that probably reinforces why a shop was hesitant.
Forum consensus seemed to be that the T1000's disc support existed for those wanting to swap out rim brakes for discs. I never found a Trek-source discussing it.
There are/were threaded adapters to bolt a disc-mount to the hub. I'd be hesitant to do that if the frame wasn't built for that load on the frame member.
#24
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Also, I knew I recalled discussion of non-Arai drum brakes. I found this link in the tandem forum : https://www.sjscycles.co.uk/brakes/k...-arai/?geoc=US
#25
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A few thoughts more- Rim brake "power" goes down with the rim's diameter all else being the same. The 20" wheel size will always have less effective rim brakes compared to 26"+ wheels.
Tandems are already well known for their slow rate of slowing down. All that extra mass but the same friction footprint as a single bike has...
Hub mounted brakes get more effective as the wheel diameter becomes smaller.
As a hobby builder guy I would first consider a chainstay mounted caliper. The chain stays likely can handle the brake forces although I'd want to think about adding reinforcement pads to the caliper mount "feet". However the clearance between the top rear point of the caliper and the seat stay's underside can be tight and might drive the real choices. And that's assuming the stay clears a rotor to begin with.
I agree that an Arai drum brake would be the easiest path. You have the hub, the stay already has a cable stop on it's underside.
Lastly real stopping will come at the front end... Andy
Tandems are already well known for their slow rate of slowing down. All that extra mass but the same friction footprint as a single bike has...
Hub mounted brakes get more effective as the wheel diameter becomes smaller.
As a hobby builder guy I would first consider a chainstay mounted caliper. The chain stays likely can handle the brake forces although I'd want to think about adding reinforcement pads to the caliper mount "feet". However the clearance between the top rear point of the caliper and the seat stay's underside can be tight and might drive the real choices. And that's assuming the stay clears a rotor to begin with.
I agree that an Arai drum brake would be the easiest path. You have the hub, the stay already has a cable stop on it's underside.
Lastly real stopping will come at the front end... Andy
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