Campagnolo Ultratorque or Powertorque on Brompton?

[chriscross1966]

Still waiting on spokes for the wheelbuilds for the big ticket changes.... rims arrived a couple of weeks ago and are a thing of beauty... 60T chainring will need a quick kiss from a file to suit the Campy PCD... vostok.bike rear triangle also ordered so I will have a comparison at some point... Chris King headset won't be here until January so front fork swap delayed until then.... Hoping to have her done for the next Swindon Smallwheels ride... will also have a look at the upcoming Origami rides...

 

[chriscross1966]

Well the spokes arrived just in time for Warlands Christmas shutdown, hopefully the Chris King headset will be here early next week and the wheels built up and then they can get cracking on the main body bits.. Still entertaining myself with the UT bottom bracket, have purchased (happy Xmas to ME!) a bottom bracket tapping and facing kit and have ordered some shim washers. This weekend I'll try and make up some "wrong way round" chainring bolts, basically a flanged tube nut that will run forward from the rear chainring position without being any deeper than the actual spiders nearest point to the frame, then wide-headed allen screws from the front. I'll make them out of M10's machined down to M6x.75, if that doesn't cure the slight rubbing as it folds I'll have to look at shimming the drive side out with the bottom bracket shims I have ordered, then refacing the non-drive side over to keep it in spec regarding bottom bracket width. The Tektro front caliper has arrived and doesn't look hard to modify to downwards pull, if I get that done this weekend I might even fit it. It looks more effective than the Brompton ones, though looks can be deceiving.... at least it is black, and that's what I want it for as much as anything else seeing as Brompton seem to be making it very difficult to get hold of Black Edition spares. The green coil-over shock has arrived, as has a carbon fibre saddle for which the austerity regarding apparent comfort is matched by the distinct lack of mass.. they can go on and I WILL get that damn seatpost shortened....

 

[chriscross1966]

OK, well valuable if slightly more pricey than I hope lesson learned.... Brompton bottom brackets aren't all that good in the big scheme of things... you need to tap and face them (Wiggle do a kit for 120 quid) and then measure the damn thing cos my one was a tad over-width and rather than go to all the effort of trimming it down I've left out the wavy pre-load washer in the Ultratorque bottom bracket. At the moment I have a bottom bracket that isn't binding and is torques up to the manufacturers recommended 55nm. In the course of doing all that I've shagged the bearings I installed somewhat, so will need to get some more, and given that I think I want to space the whole thing over by a millimetre (i have some bottom bracket shims on the way) to stop the inside of the spider fouling on the rear frame as it folds, I think I need to come up with a powertool method of trimming that BB down.... I'm thinking of some way to mount a shell endmill on a drill might work or some sort of fixed-radius holder that I can mount on the tapping mandrell and use a smaller high-speed cutter to slim the bracket down....plan A is to go through my stuff and see if I have a suitable shell endmill anywhere.... I could swear I saw a pile of them a few weeks back in one of the sheds...

 

[chriscross1966]

Aaaaaand...... now I realise I've been a cretin, indeed, that is mildly insulting to cretins..... I didn't read the spec sheets enough when I was getting this stuff together (who reads manuals anyway).... I've put a pair of 6805's in there.... they should be 6805N's (bugger 2).... the difference is a whole millimetre... that's where all the binding has come from... anyway, correct bearings on order now, the good news is that that should allow me to space the bracket over to the right a couple of millimetres with shims and get away with it.... (hurrah3).... and I won;t have to manufacture some kind of powertool bracket slimmer (hurrah4)

 

[chriscross1966]

In further news, Henrietta has had her seatpost cut down to the correct length for me (slightly shorter than a extended post, but longer than a standard one), she has her new suspension unit with a racing green spring over the damper and the carbon fibre saddle is slightly more comfortable than I expected (which isn't hard, though the saddle is). I am noticing that the overall weight has come down now. Once all the mods are done I'll weigh her properly.... the aim is to get an 11-speed that weighs no more than the original 3-speed and preferably somewhat less...

 

[chriscross1966]

In an exciting development, Henrietta is at Warlands, hopefully having her 11-speed back-end fitted. Still wiating on a Chris King headset to arrive before the front gets done...

 

[chriscross1966]

Warlands had an apparently tough day fitting such a large hub into such tiny rims with such stiff spokes, so although the wheel got built, they didn't have time to fit it. It is a thing of wonder though, and we're booked back in for monday.

Back to the bottom bracket and having pulled the wrong bearings out and put a cheap set of 6805N-2RS in there I've managed to shim over the drive side cup 1.5mm and there might be a bit more to come, but even that has massively improved the fouling issue. Waiting on some 0.3mm shims to arrive as I have, theoretically, 0.3 to 0.5mm of axial float in the crank.

 

[chriscross1966]

Correction, Tuesday, Andy doesn't work Mondays :-).... Anyway these are the newly made chainring nuts.... Hurrah for having a lathe at home... The bolts are from the KCNC set

Chainring bolts

• chriscross1966
• 8 Jan 2017

Chainring nuts

• chriscross1966
• 8 Jan 2017

 

[chriscross1966]

Just had a test ride with these and a 2mm shim stack.. And its perfect as far as I can tell... No knocks, creaks or squeaks, no frame fouling when folding... Woohoo! Took long enough :-)

 

[Gavrassaf]

I also tried today to install my record 10 speed ultra tourqe crankset on my brompton , put the cups but the bolts as I fold the bike touch the frame ... can you describe what you did eventually? Did you put only shims between the arms and the cups ?

 

[chriscross1966]

I put a 2mm shim under the drive side cup between the frame and the cup (after facing the drive side of the bracket flat and square) on Centaur and Chorus Carbon Compact cranks fitted with a 60t ring this gives enough clearance. I ended up making my own chainring screws, but have since found that by trimming an M10 penny washer it will fit on the inner ring plate and allow for normal chainring screws. The one behind the crank will need to be replaced with a shorter one, they are available, I made mine. You have to get rid of the spring/wavy washer and face the non-drive side of the bracket until it all torques up without binding.

 

[Gavrassaf]

Thanks Chris
So there is no way to fit the 53 chain ring ? Btw its no matter which chain ring I will put the screws will stay at the same spot and will avoid frame folding , I also tried to tourqe the crank w/o the left arm spring but it stack and won't moving freely any more , i put as you said the 2mm shim on crank side between the cup and frame , I will look for the screws you suggested ...

 

[chriscross1966]

53 will fit, I've had a 50 and a 60 on that crank. I will try and get pictures if my setup. What is the screw head fouling on? My Brompton does have a Vostok rear triangle (titanium, takes 135mm hubs), but I've had the same crank setup with the Kinetics one and both the standard steel and titanium ones