Hello all,
I have done a pretty thorough search of the forum and read quite a bit about the UCM and d’Brake options for going disc with a non-tabbed frame - but seeing as I have a couple of questions regarding my Triton Triple frame I thought it might be useful to ‘house’ them all under a new thread.
I’ve read the specs of the frame and see it says max 29" tyre is 2.5" yet I seem to remember reading it could take a Knard. Am I right? And what is the max if running a fat 24"? I know that at 26" it is 3.8 - any chance it could take a 24x4 on a LM rim?
Regarding brakes: do Maguras fit if using a Surly LM rim without special mounts or do you need something like the Tensils that allow more sideways adjustment?
With discs I see that the MountainUni UCM is probably the best choice for a Triton. With the Triple I was told some filing is needed to get it to fit. I know this may be a tad demanding of me, but could someone post a pic of their set up?
Again with the d’Brake option specifically with Tritons (and even more specifically with the Triple) is my only option to stack up washers to create a planar surface and tighten down the bracket side/arm to direct the braking force into the frame? Or is there some filing needed also. A photo would be lovely if some kind soul would oblige
I do like disc brakes from riding my Oregon and KH36(tabbed) but I’m a little cautious to rig something up that may not last or even damage the superb Triton - so I am being extra careful here before deciding on a disc set up over the ‘old school’ Magura route. (With the Triple a Magura set up does have some sense and a kind of charm…)
I will appreciate any tips or info people can give me - and if I do go the disc route I’ll make a little video tutorial on how to set up an outboard disc with with Spirits using either a UCM or d’Brake
I don’t remember a setup with a Large Marge 24 and Magura but I know for sure that it takes a Large Marge 26 with a 26x4 tire without any problem including using Magura with the regular brackets (translation drop down on the top of the right column). I don’t see why it wouldn’t work with the 24 inches version as I am sure they spec’ed their frame when the Large Marge was out and available. You can double check the distance between the frame’s legs at the 26in magura mount and the 24in magura mount. The Large Marge has a fixed width, so if the measurements are the same, you’re golden
And as for the D’Brake or MountainUni UCM, you won’t need to use shim because the frame as a flat surface you can tighten against (like a KH). At least for the MountainUni UCM, they have a v2 version that is compatible out of the box with Triton frames so that should be the way to go if you are unsure about filling a D’Brake.
And finally, don’t be shy with your frame, you will have a hard time really damaging titanium especially just with a caliper & a disc in the even a D’Brake failure (your bones may not be as forgiving on a bad landing… ).
I thought filing down the mountainuni ucm caliper would be demanding, so I was hesitant at first. But I just got another ucm set-up and it took me less than 10 minutes to do. Just get a rounded aluminum filer at any hard wear store for a few bucks and grade down the holes a little but until your bolts can be properly fitted to the bottom bracket and frame. My caliper is set-up to my muni right now, but I may be getting my frame powdercoated soon, in which case I’ll take pictures of how and what I did. It probably won’t be until 1-2 weeks though.
I’m also trying out the magura rim brakes on another build just to see if I prefer disc or rim brakes. The only limitation I’ve found in using the mountainuni set-up is the fact that SINZ cranks do not exceed 145mm (as far as I have found…does anyone know if there are 150+ sinz cranks out there?). I would definitely prefer more leverage. However, I do like the speed of the 145mm vs. 165 so maybe I’ll get used to it. It’s all a matter of preference. Jeff is really helpful at Mountainuni and Bryce is really helpful with Maguras. Whichever way you go, keep us updated with lots of pics!!
Since the Triton Frames have machined bearing housings (and not the cheap stamped sheet metal ones) there is already the needed planar surface. No washers or adaptors needed.
Machined bearing housings:
Sheet metal beraing housings:
For sheet metal beraing housings you need washers or an adapter
If you’d consider it, longer ISIS cranks have been shortened for use on recumbents, and by special needs riders, kids on the back of tandems, etc. E.g., this guy, who’s a long-time stalwart of various cycling lists:
It looks like he could do 150-ish 110 bcd ISIS cranks of some kind if not Sinz. The site shows FSA Gossamer cranks shortened to 153.5mm with 130 bcd–the hole spacing for the chainrings/MountainUni disc–but I’ve seen them @110.
Hello Again
I checked how a d’Brake lines up with my triton and the holes are way off and it looks like it would need quite a bit of filing to get them to line up properly, and even then I don’t think I’d trust it to last long.
I will go with a UCM (hopefully V2 so I can use a 160mm disk)…
This then got me thinking about Spirits and disk clearance with the angled triton frame legs. They are not dead straight up from the bearing holders like the normal Tritons or KHs. Does the disk clear the frame when using Spirits? I have seen a Triple with Sinz and MountainUni rotors, but don’t seem to recall a Spirit set up.
When I get a chance I will take the crank with rotor off my KH36 and test to see the clearance I get in the Triton Triple. I hope it won’t be as tight as I think it could be.
Maybe it’s something to do with the what seems to be a shorter axle on the Nimbus 32h as it has a 6mm spacer when it should be an 8mm - when I put an 8mm the axle left sticking out for the crank itself looked way to short so I used a 6mm and that fits perfectly. Now curious if other users of the Nimbus 32h ISIS hub have come across the same thing? And could this make fitting Spirits problematic / impossible clearance wise?
I haven’t seen a Triton fram IRL but I have seen Sinz & Spirit cranks. Both have the disk mount set back compared to the inner edge of the crank. And even if the Sinz has a slightly more important setback, the MountainUni rotor is a 180mm. Going for a 160mm rotor & Spirit sound safe. And if you already have some to test, you’re golden
@Sidd - Thanks for your input - yes I will just try it out myself, but wanted to see if someone knew of any problems I might run into… Cheers
@bouin - How can I tell what version of the triple I have is? And regarding holes, do you mean on the D’Brake/UCM - they they need some modification, or is there something “wrong” with the older frames that was later corrected? Thanks a lot
Older Triton had the holes in the middle of bearing cap and not in the axis of the bearing, Macduni had this issue. Can you put a close photo of your frame ?
Photos regarding disk clearance on Triple.
It just about clears the frame when crank is mounted with a 6mm spacer. I get around 2mm. If I were to use a 180mm rotor in stead of the 160mm I believe the disk would rub on the frame. It could all be solved with an 8mm spacer moving the crank out a bit more, but when I put one on the remaining axle looked way to short.
– Am I right in thinking there should be enough axle to go all the way into the crank splines (up to the space were the threads start for the removal bolt)?
@bouin - thanks a lot, yes I will take out my wheel later this week (away now with work) and get a close up pic of the bearing mounts. Curious about this…
Maybe Maguras would be the simplest way to go, but I would like to get a disk option working with this lovely frame and LM wheel
Here is a close up of the bearing cups. I suspect I do have the off centre version of the frame. I can see that the bearings are not in line with the bolt holes of the frame.
What are the downsides of this set up? Apart from problems with disk brake set ups using UCM or d’Brake. Are the bearings under more stress seeing as the frame isn’t centred above them? Does this arrangement mean a weaker set up overall?
I am curious what the thinking was behind this to make things this way…
It’is better to have the bearing in line with bolts for bearing stress but not an issue with Triton frame as bearing holders are machined with precision. Your frame is corresponding to original design, Macduni attapted a Dbrake on such frame but not easily
The bearing weight is distributed from the seat down
I don’t believe there’s any more bearing pressure with a Brake hanger, as the majority of weight is still distributed from the seat downward. The only duress the UCM comes under is under braking. So as long as UCM tight and you have the same gap between thread inserts on each side, you should never have any issues. bwrightback has described the rat tail file modification for Triton frame to a T.
Here is a close up of the bearing cups. I suspect I do have the off centre version of the frame. I can see that the bearings are not in line with the bolt holes of the frame.
What are the downsides of this set up? Apart from problems with disk brake set ups using UCM or d’Brake. Are the bearings under more stress seeing as the frame isn’t centred above them? Does this arrangement mean a weaker set up overall?
I am curious what the thinking was behind this to make things this way…
I see, thanks - I wasn’t actually concerned about the UCM stressing the bearings. I was just curious about the off centre alignment of this older triton frame, and before that a bit about getting disk clearance with the splayed out frame legs of the triple. But now it all looks set to be possible and I see that UCM is the way to go. Did you get my email about ordering a V2 UCM? The max size rotor I can run will be 160mm as anything bigger will rub on the frame.
Hi Felix, No V2 UCM is in the works, if it ain’t broke don’t fix it. Not really understanding the 160 vs 180 issue. The diameter of the rotor shouldn’t affect any frame rub. On some applications, I have found the need to shave off the inside head of the CRB’s that come very close to the frame stantion, even with a 6mm spacer. But my kits only use 180 rotors, as that’s what was fabricated to mate up to the SINZ 5 bolt cranks. If 160 is the biggest you want, then the KH Spirits is likely your only option.
Hi Jeff (mountainuni1, right?)
Thanks for your response
Right - my concern about using a 180 rotor is that I believe it will rub the frame as the legs of the triton are not straight but angle out slightly. With the 160 rotor pictured a few posts back I got just about 2mm clearance but if the disk grew even a little in size this clearance would decrease to less that 1mm. Too close for comfort.
I realise your UCM works with SINZ 180 rotor and nothing smaller… I assumed that this would be it wouldn’t with with Spirits using 160 - or have I now got that wrong? From your response I guess I have as I now can’t logically see why KH spirits and a 160 rotor and the UCM wouldn’t chum up happily together and play ball if I have then I’m happy to get the UCM and use it with the KH cranks, and do a little filing to get it to fit. Sounds like a nice option.
I saw on your site a picture with a diagram of the UCM and there it did state that it would work with 160 to 200mm ISO adapters, but I got a tad confused as others had stated (as does your site’s main info) that 180 was the minimum (but I guess they were talking just about SINZ)
So when it comes to placing an order I should just do it via your website? How long does your international shipping take to Czech?
Piggy-backing on this thread for an additional question.
Context:
A Triton Triple frame with a 65mm rim and a 26x4.0 tire. When riding, I get some tire rub on the right side.
Wheel trueness is out because I was able to try a second wheelset in (same side for the rub). It could be tire deformation but I guess it would be consistent on both sides (especially when cranking hard) and less a problem at higher pressure.
With a Surly Nate 3.8 27tpi @ ~ 30psi: rubs on the right when cranking hard
With a Schwalbe Jumbo Jim 4.0 SnakeSkin @ ~ 30psi: rubs on the right almost all the time
Questions:
am I just unlucky and the Triton Triple has a clearance so tight that I am out of luck and should get used to it ?
or is it possible that the frame has a problem (not straight or flexing) ?
For reference, I have been running with the Nate in this frame for a while and I only noticed some rub recently.
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