January 5, 201412 yr hello all, As I ordered few motors to be build to save a bit of money, and that I have motor to lace to brompton rim, I create a thread to reference motors data so we can't create wheel much more easily and faster. I found this calculator quite handy: http://www.newsonsportec.com/images/calculate/calculator_01.jpg http://www.newsonsportec.com/images/calculate/calculator_02.jpg http://www.newsonsportec.com/images/calculate/calculator_04.jpg Newsonsportec Inc., Ltd. I have BPM and Cute100H to lace to brompton rim. Data for the BPM: OLD: 134mm L: 41mm R: 45mm T: 4.5mm Left side: Number of spokes: 18 Flange diameter: 168mm Spoke hole diameter: 5mm Right side: Number of spokes: 18 Flange diameter: 168mm Spoke hole diameter: 5mm Apparently this company can also provide spokes and nipples. I'm in touch with them.
January 5, 201412 yr Author I don't want to be limited by the brompton rim, so I'm using this 36h rim http://www.sjscycles.co.uk/sun-cr18-16-x-1-3-8-(349)-abt-alloy-rim-silver-36-hole-prod8542/
January 5, 201412 yr Author Data for the Cute100H: OLD: 100mm L: 30mm R: 24mm T: 4mm Left side: Number of spokes: 18 Flange diameter: 105mm (not completely sure) Spoke hole diameter: 4.5mm Right side: Number of spokes: 18 Flange diameter: 105mm (not completely sure) Spoke hole diameter: 4.5mm
January 5, 201412 yr I don't want to be limited by the brompton rim, so I'm using this 36h rim http://www.sjscycles.co.uk/sun-cr18-16-x-1-3-8-(349)-abt-alloy-rim-silver-36-hole-prod8542/ I hope you have found a good way to put the tyre on This rim is killing me lol Pat
January 5, 201412 yr Author no I haven't found one. but I'm thinking to use normal tyre rather than the marathon plus
January 6, 201412 yr I now buy my motors with 28H so I can use either the old or new Brompton double wall rims. I gave up a year or two ago with Sun rims as getting tyres on or off their 36H/16" ones was a nightmare. I could do it, but usually you ended up damaging the bead after a few tyre exchanges. I do have a couple of 36H Brompton rims though, for emergency projects Jerry
January 6, 201412 yr I now buy my motors with 28H so I can use either the old or new Brompton double wall rims. I gave up a year or two ago with Sun rims as getting tyres on or off their 36H/16" ones was a nightmare. I could do it, but usually you ended up damaging the bead after a few tyre exchanges. I do have a couple of 36H Brompton rims though, for emergency projects Jerry What rim is it may I ask? Pat
January 6, 201412 yr One of the old Brompton single walled ones (which you could get as a blank) and then professionally drilled for 36H. I have two actually a brand new one and one with about 800 miles on it. I would offer it but as they are like hens teeth I really would like to keep them. Jerry
January 6, 201412 yr Hi Jerry, I know they are like gold but would you mind to offer one to me? I would not mind to have the used one. I have not got any spare Pat
January 6, 201412 yr I guess I could sell you the used one. Let me dig it out and check that it is still in my workshop. Probably best to PM me as I don't want to hijack the thread. Regards Jerry
January 6, 201412 yr Hi Jerry, Thanks. There was an error when I sent you the PM Not to worry. Please let me know when you find the rim btw I am using this link for spoke calculation Edd, an easy to use spoke calculator What is the main difference? Pat
January 6, 201412 yr Author If any of you order also rim and nipples, let's do that together to reduce chance of mistake and costs
January 11, 201412 yr Hi my SJS 36 hole rim for Q85 Brompton conversion arrived today. I got the local bike shop to measure and lace my full size conversion but thought I might try this time. So questions - I'm not sure how accurate measurements need to be - how should I measure? Are some callipers best? Or has anyone already got Q85 measurements? I don't know why this info isn't provided with the motor! Cheers
January 11, 201412 yr The Q85 has its spokes on a 108mm PCD with the flanges each 20mm from the centre, so now you need to measure the ERD. If you don't know it already, measure the inside diameter and add on 5mm, or search through Jerrysimon's posts. I'm sure it's in there somewhere. For other Q-series motors: Q75 is 98mm and 80mm PCD. Flanges are each 25.5mm fom the centre Q100, Q100H 108mm PCD. Flanges. Front (disc version) flanges each 21mm from the centre. Rear disc ver. Flanges 20mm and 27mm from centre. Q100C 108mm PCD. Flanges 33.5mm and 13.5mm from centre.
January 11, 201412 yr Author Hey dave, How come your Q100H measurement for the front wheel are different to mine? Would that be an issue if length is not perfect?
January 11, 201412 yr What measurements did you use? Sorry, just seen them above. I'll have to do some calcs Do you know the ERD of the rim? It seems that there's several different ones.
January 12, 201412 yr For one-cross, they should be 73mm and 75.5mm for the back or 73.5mm for a front motor. As long as you're within a few mm, you should be OK. What size did you order?
January 12, 201412 yr Author I haven't ordered yet. I wanted to be sure. I have this data from the calculator: I was measuring different width on the left (30mm) and right size (24mm). But also, this calculator indicates 242.1mm spoke length for 1 cross?? What did I do wrong?
January 12, 201412 yr Sorry, I made a mistake above - too late at night! I''ve used two calculators, which give: 121.4 and 120.6 121.1 and 122.5 The hub is 108mm and the ERD is 340. That means the radial gap between the two is (340 - 108)/2 = 116mm, which would be the 0-cross size The length of the spokes will be a bit longer than that because they'll be at a slight angle, so 121mm seems about right. Your 250mm is more than twice as long as the gap! In fact I can see that all those spoke lengths are exactly double what they should be, but I can't see why. Try changing the number of spokes to 36 to see what happens.
January 12, 201412 yr Sorry, I made a mistake above - too late at night! 121.1 and 122.5 The hub is 108mm and the ERD is 340. That means the radial gap between the two is (340 - 108)/2 = 116mm, which would be the 0-cross size . Your 250mm is more than twice as long as the gap! In fact I can see that all those spoke lengths are exactly double what they should be, but I can't see why. Try changing the number of spokes to 36 to see what happens. Hmmmm.......
January 12, 201412 yr Author i tried to change the measures but I have the same results... I'm asking seller for confirmation
January 12, 201412 yr Hubs front Left flange 108⌀ Right flange 108⌀ Center to left flange 20 Center to right flange 20 Spoke hole 4.5⌀ Rims Sun CR18 ERD 340 OSB 0 Spokes 36 Crosses 1 Spoke length left 120.3 mm Spoke length right 120.3 mm I hope this is right! I note the Q85 spoke holes are about 3mm and the Sun CR18 rim holes are 4 or 4.5mm. Does this matter?
January 14, 201412 yr I don't know if the Q85 manufacturer keeps their hub dimensions the same over time. But I know that Keyde doesn't. The first front hub motor I ordered last summer for my Brompton had a 90mm PCD. I ordered another one six months later and had spokes cut assuming that the hub would be identical to the first one. Wrong. The second motor had a redesigned, slightly beefier flange with a 93mm PCD. Fortunately, that only made a ~1mm difference in the required spoke length with the 1-cross pattern I was going to lace.
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