RM125B final gearing

[Montynut]

Can anyone tell me what gearing to put on an RM125B - using 428 chain or should I fit 520?

[Ted]

Straight from the Suzuki bible   

 REAR     59 T standard  57 T or 61 T optional

FRONT    14 T standard   13 T optional

CHAIN    429 x126


Steer clear of the OPTIONAL parts....i can see nothing but trouble

I`m keeping the smaller chain on mine

[John Orchard]

When I was running the 14/59 I couldn't change gears fast enough, I think with the extra power it'll pull the 15/59 perfectly, that's why I just fitted that.  Interested to hear other idea's.

[Noel]

AS with most 125's it will depend on the track,
lets take "Lakes", on My RM "T"  tight technical sections  needed clutching through,(Low first) long up hills with varying grade, you need the gears as close as possible ( I put on 13 /52 )because trying to select another gear at speed up the hill can see you dropping out of the band,I went up a couple on the back sprocket just for that track ,most of the others may be  ok with taller gearing
Nepean Dirt track  I needed to take up couple off the back (13 /47)

Dissclaimer:
up till this year had 49 on back
I think the front is a 13 but may be a 14
( RM "T" with 520 chain)
going to the 52 teeth on back of 'T" required a small mod to the chain guide at rear