OzVMX Forum
Clubroom => Tech Talk => Topic started by: pmc57 on March 30, 2010, 10:24:07 pm
-
What's the standard length shock for a Suzuki RM250B? Mine are what I think are standard Suzuki's #62100-41650 and are 380mm eye to eye. My feelings are they could be about 10mm-15mm too short by the way the bike sits at the rear. There's doesn't appear to be any resting sag at the rear.
These shocks were rebuilt a few years ago so condition wise they are pretty good, however I also seem to think the springs may be too hard, I've got the spring circlips on the least compression setting now. There's no leaks or anything like that and dampening seems to work fine. Are optional (softer) springs readily available for these shocks?
I'm considering at taking them into a Brisbane shocky repairer in the next week or so for a "service" and to discuss my issue, so any advise on getting the full package working better before I go down this track would be helpful.
If I bit the bullet and bought some after market shocks, would I notice much difference? Any suggestions on where to go without breaking the bank.
pmc57
-
Ring me tomorrow Pete, I've got the lenght's written down at work...... I think 370 or 375mm from memory.
-
15.25" or 387mm standard but aftermarket are sometimes abit longer.
-
The 250B is listed as 14.75"(375mm) and the 250A had 15.5"(393mm) shocks..
-
something many people don't realize is the std RM Kayaba shocks have 2 damping settings as well as the 3 spring preload settings. May not help in this instance but it's worth playing with as it does make a difference to the ride and it also pays to double check they are on the same settings ;)
-
a friend of mine wants to know
rm125b shock length eye to eye
as well ???
-
Just for reference, the Ohlins book says 390mm (15.354")
and
Part # = 62100-41650
Part Description = ABSORBER ASSEMBLY,REAR SHOCK
Model Count = 3
RM250B 1977
RM250C 1978
RM370B 1977
-
OK boys, write this down........RM125, 250, 370A MODELS= 360mm.........RM125, 250, 370B MODELS= 375mm..........RM125, 250, 400C MODELS= 407mm........RM125N and T MODELS=417mm....... RM250, 400 N and T MODELS=394mm......lets not turn this into a footpeg saga so all you weido Suzuki nutjobs go and look at the YZ500 pictures on the Yamaha page..... "whats the best bigblock Yamaha" and chill out!!!!!!
-
Just for reference, the Ohlins book says 390mm (15.354")
and
Part # = 62100-41650
Part Description = ABSORBER ASSEMBLY,REAR SHOCK
Model Count = 3
RM250B 1977
RM250C 1978
RM370B 1977
works performance book is close to that - 15.25" /387mm
-
I measure .......
RM125 B part no 62100-41311 @ 375mm
RM125 C part no 62100-41313 @ 375mm with the C models having the adjustable rebound.
-
The shock lengths that i quoted were straight from the Fox suspension book.
There is always the real possibility that the shock lengths quoted by some aftermarket companies for the shocks they build will be for longer shocks to increase rear wheel travel as well as the performance.
-
The shock lengths that i quoted were straight from the Fox suspension book.
There is always the real possibility that the shock lengths quoted by some aftermarket companies for the shocks they build will be for longer shocks to increase rear wheel travel as well as the performance.
Works P havee 2 options stock - 15.25 and longer than stock 16" ????????
-
Davey I dunno where you got those measurements from but regardless what any book says my RM400 shocks from new were/are 394mm. It is also not possible I have 250/400N shocks fitted as the mounting bolts on the N/T models are 8mm and the early jobs are all 10mm hence the N/T shocks don't fit the A/B or C's. The 375mm on the 125B is 100% accurate as I just measured mine and double checked all the numbers to be sure they were the correct units ;)
-
Doc, TMBill has a Suzuki bible and that's where the measurements have come from.......now go and look at the YZ500.
-
Well Mr Bill's bible is telling fibies sorry John :D as for the Yamaha, that's devil worshiping!! ::) but, I may find my way over to the darkside eventually for a sneaky peek. Had an OW40 1980 250 offered to me from a guy in the US recently ;) Unrestored but 98% complete $13000US excluding shipping and vat fee bla bla but nah..only thing I liked about it was the colour..yellow :D
-
Wow so much input, thanks everyone.
OK looks like the shocks are correct for the bike, now all I need to do is get them working better. I'll talk to RAD's next week.
Doc, I think the shocks with the internal dampening adjustment may be the 1978-C2 shocks, I've tried this on mine, pushed shafts all the way in without springs and there's no tell tale clicks. While they're at RAD's I'll get them to double check.
-
You dont push the shafts in like a Koni, you pull them out hard against the top out rubber then rotate the shaft.