77/78 RM 100/125 experts needed

[LWC82PE]

what is the difference between 77 and 78 Rm 100 and the 77 & 78 RM125 rear hubs? are they interchangeable?

[lukeb1961]

77 RM100 rear hub is the TS185 hub. Shared with RM125 A/B.

78 RM100 was the hub shared by RM125C and the PE175 C/N.

[Doc]

Spot on Luke and also the C used a floating rear brake setup while the B had the brake stay bolted under the swingarm. The RM100/125B model rear hub is shared by 30 something models ranging from 100cc to 185cc it's just some are silver and some painted black  

[LWC82PE]

yeah but what is the physical difference between the C and B hub? ive got a 77 TS/RM hub but i need to know what is the difference with the hub compared to 78 RM 100/125/PE 175 hub

is the floating rear brake just a difference in brake plate? if so why different part numbers for 77 RM 125 hub and 78 RM 125 hub?

can i use a 78 hub with a 77 rim? this is why i need to know what the difference is between the 2 hubs


Part # = 64110-41320
Part Description = HUB COMP,REAR
Model Count = 4
PE175C 1978
PE175N 1979
RM100C 1978 
RM125C 1978


Part # = 64110-38001
Part Description = HUB,REAR WHEEL
Model Count = 31
DS100C 1978
DS100N 1979
DS100T 1980
DS100X 1981
DS125C 1978 
DS125N 1979
DS125T 1980
DS125X 1981 
DS185C 1978
DS185N 1979
DS185T 1980
RL250L 1974
RL250M 1975
RM100A 1976 
RM100B 1977 
RM125A 1976 
RM125B 1977
RM125-M 1975
TS100C 1978
TS100N 1979
TS100T 1980
TS100X 1981
TS125C 1978
TS125ERT 1980
TS125N 1979
TS125X 1984
TS185B 1977
TS185C 1978
TS185N 1979
TS185T 1980
TS185X 1981

[lukeb1961]

lots of photos sent!
Luke

[Doc]

have a look at the pictures at alphasports Leith, the hub is completely different. The sprocket mounting is way bigger and I don't believe the A/B backing plate will work in the C wheel due to the different internal offset even though they may share the same brake shoes. The A/B or TS hubs offer far more sprocket options also from 428 pitch through to 520 so I think it would be a step backwards to fit a C or PE C/N wheel if it were to somehow fit

[LWC82PE]

gees thanks Luke i will check now

[lukeb1961]

I have a RM125C/PE175C rear wheel up on the bench right now if you need measurements.
Luke

[LWC82PE]

Ok I can see the difference now. What I was trying to determine is if the 78 onwards 125/175 rim will fit the earlier hub. I think its worth a gamble as a few old Sun rim catalogues I have list same 185x18 rear rim for RM 125 A,B,C,N,T

if i think i need hub dimensions i will let you know tomorrow Luke and then i think that will answer everything.

[Doc]

so long as the rim is 36 hole she'll fit just fine

[LWC82PE]

not quite, you gotta look out for different spoke angles

[Doc]

Have put together over a dozen wheels for TS/RM/TM's and kawasaki's and never had a problem as most Suzuki trailbike/MX hubs runs very similar sizes which equates to much the same angle of the dangles it would be something pretty weird such as a late model or roady rim that'll give you problems if they have either a much smaller or a much larger hub size fitted originally.