Motors dimension for wheel building

[cwah]

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:

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.

 

[Deleted member 4366]

Don't Brompton rims only have 28 holes, or have you found some 36 hole ones?

 

[cwah]

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/

 

[cwah]

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

 

[patpatbut]

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

 

[cwah]

no I haven't found one. but I'm thinking to use normal tyre rather than the marathon plus

 

[jerrysimon]

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

 

[patpatbut]

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

 

[jerrysimon]

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

 

[patpatbut]

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

 

[jerrysimon]

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

 

[patpatbut]

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

 

[cwah]

If any of you order also rim and nipples, let's do that together to reduce chance of mistake and costs

 

[Joneser]

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

 

[Deleted member 4366]

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.

 

[cwah]

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?

 

[Deleted member 4366]

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.

 

[cwah]

Yeah I'll use the brompton 36h rim at 340mm erd.

 

[Deleted member 4366]

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?

 

[cwah]

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?