Hey guys
recently picked up a set of original showa 49mm forks for my rm250. Bored out the clamps and they fit perfectly. The issue I’m having is with the Axle and spacers. These forks came off of an 08 rmz450 so I ordered a rmz hub/spokes/rim/axle spacers and built it and when I went to install the wheel onto the bike, I’ve noticed a few problems;
1. the axle is the correct thickness (22mm) but it isn’t long enough (228mm)
2. the stock rmz spacers aren’t the right length
3. The rm/rmz caliper fits but it makes the wheel sit closer to the brake side
my rm axle is long enough 238mm but it is 20mm instead of 22mm.
so I’ve realized that the these forks aren’t for an rmz but were fitted on the bike and maybe used a Honda/kawi wheel/hub/spacer/brake set up.
just curious if any of you guys are familiar with these forks and if there’s a potential wheel/hub/spacer/brake combo that would work with these.
Thanks in advance
I would say one of the main possible issues is your clamps, the RM and RMZ clamps would likely have had different spacing between the fork legs which is why your RM axle is long enough and your RMZ one isn’t.
https://www.vitalmx.com/forums/Tech-Help-Race-Shop,42/RMZ-front-end-swa…
Thanks for the reply. I also considered this but what’s strange is that if I butt the oem rmz spacer up to the lug, the rotor would hit the fork leg. Which has me thinking the lugs aren’t for a suzuki/rmz. I haven’t been able to find anything about the rmz/rm clamps having width differences, only different offsets. It’s been a mind bender so far.
Luckily, I’m still in touch with a vital member that I purchased them from and he has been super helpful and is going to check this weekend. I’ll update this thread asap.
The Shop
DeCal Works Huge Plastic Inventory of UFO and Polisport kits.
Luxon 4-Post Bar Mounts
$189.95 - $239.95
Free shipping: VITALMX
Very odd. Those are definitely RMZ fork feet as all other brands don't have that style of fork guard fitment. The wheel spacers also look correct (RMZ).
I agree with above it could be the clamps are too wide.
What year is your RM?
I have a 48mm KYB RMZ Fork on my RM250, I will measure the foot to foot inner width when I'm at my bike next at the weekend and let you know the measurement
hey Russ,
They’re the 04-07 RM250 Universal branded clamps. The fork guards and the caliper fits perfectly so in that case based on what you said, they are suzuki lugs. It just seems like the oem rmz spacer still wouldn’t fit right even if the forks were closer to eachother as the rotor would basically be on the leg. I appreciate the help
Is the original RM axle you have the one you were using with the OEM fork set up before? What year is your RM?
Trying to wrack my brains here as I've owned RMZ450's and RM250's. And on the RM250 I've fitted Showa A Kit, Showa SFF TAC and KYB 48mm RMZ forks using RM standard clamps, Neken RMZ clamps and Pro Circuit RMZ clamps and have never had this issue.
I know the axle length is different between RM and RMZ, but I don't remember the clamp diameter being different? Are you sure your RM axle is correct?
To me it sounds like your set up needs an RM wheel and spacers, as the RMZ set up is too narrow. The RM hub uses spacers that way way wider than RMZ. Try and fit your RM wheel and spacers with the longer RM axle and see how that goes?
It’s an 05 rm250 with the stock showas and axle. The rm axle is the proper length but the issue is that it’s 20mm so it’s too narrow for the brake side fork lug and there’s a lot of play. I just tried putting the rm wheel/spacers/axle on but the wheel is still closer to the brake side and if the forks were to compress all of the way, it’d hit the rotor.
left is rmz and right is rm
Sorry yeah my bad, the fork foot clamp diameter is the same on RM and RMZ axles but the hub/bearing/spacer diameter is smaller.
Really is an odd one!
The last few days I’ve been searching the depths of the internet to see if there’s any insight and I’ve yet to find something concrete. My suspension guy apparently worked on this stuff back in the day and mentioned how stiff the springs were (.58) and even he’s confused with this current issue. My guess is that they might have been factory or something really close to it.
At this point, I’m thinking I should just buy the rest of the front end from the seller. I’ll speak to him this weekend to find out more.
Remember the "free side" lug floats, so even if the axle is short, it should just sit deeper in the lug if the clamp spacing is off. Being that it's on the caliper side, it means that the spacer between your wheel and the lug is the culprit. They probably aren't RM lugs and something like a kx250f, as they used the same front caliper bolt patterns as Suzuki for awhile. But for an immediate solution, you can simply measure the gap between the wheel spacer and the lug when it's all assembled with the rotor sitting at the correct spacing and have a longer wheel spacer made. Once you know what the dimensions need to be for a new wheel spacer, that's a $30-50 job at most machine shops to make you one of those.
Update:
I was never able to figure out what I needed in order to make it work. Good news is that the seller has the correct axle/spacer/hub combo and sold them to me. The fork spacing ended up being correct and the axle he has will bolt and allow me to run the set up. It’s 22mm thick and 9-7/16” (240mm) in length which is the length of the rm and the width of the rmz.
All in all, a strange issue but glad I was able to get it remedied. If you’re ever in a situation like this, you’re probably better off buying the whole front end from the seller if you’re not 100% sure they’ll fit with your current set up. I didn’t buy the caliper or triples from him but had my triples bored out and they fit nicely.
Post a reply to: Showa RG3 AKit fitment issues rm250/rmz