Two Stroke Motocross
Two Stroke Motocross Forum => Technical => Topic started by: FatBiker on June 03, 2010, 09:10:11 PM
-
I'm kind of a tight wad so keep that in mind. Should I have this welded or replaced? I'm a very mild rider if that makes any difference. It's off of an '82 RM 250.
(http://i.imagehost.org/t/0668/IMG_0106.jpg) (http://i.imagehost.org/view/0668/IMG_0106)
-
Your rim has told you it is time for it to retire. Get a new one off Ebay.
-
yeah, that looks pretty bad
-
That rim is toast....replace it before it hurts you :o
-
i think the fatigue life of the rim has been reached :o usually when you weld a rim it cracks again right next to the weld.
-
I have a riding buddy who welded a crack just like that one.No matter how hard I tried I could never true it up. The weigth of the weld through it horribly out of balance.It did hold but the shaking finally drove him nuts it was on the front. I agree, start soaking the nipples with penatrating oil while you find a replacement.
-
...yeah really bad. We have both a MIG and TIG welder and just do not fool with these rims anymore. If there is a slight crack on the sides that does not extend clear-across...you have a chance. Otherwise, buy a new wheel or pay a welding "hero" $150 to weld-it. Bro, I am also really cheap, but sometimes you get what you pay for...
-
It's unanimous, I'm getting a new rim. Is it all that hard to get one true or should I just buck up and let the shop do it? I've never done one. I'm not afraid to build a truing stand either.
-
I've done a few.As a matter of fact,my 11 yr old daughter did the rims on her LEM from a complete disassembly(with some instruction)-but don't let that bother you :D
Seriously,if you're the patient type you can do it.The key is to know which side spokes go where and take measurements with a straightedge across the rim to your sprocket or brake or whatever to get the proper offset before you disassemble.Digital cameras are your friend for the first time as well.
-
Put your rim back on the bike and measure the position from the sides (front rim right?). Loosely tape the spokes where they cross and loosen the spoke nipples. You should be able to wiggle the rim loose without disturbing things too much.Mount the new rim loosely back on the wheel and reinstall on the bike (bike is on a stand of course). Tape a pencil or pen to each side of the fork adjacent the rim (dial indicators are better ) and gradually tighten the spoke nipples (a little antiseize on the threads helps).Try to concentrate on loose spokes initially and remember the position measurements.You should only start to really tighten the nipples near the end of the process and you are always "pulling the rim" into position from the side opposite you want to move.There is a torque specification for spoke tension,tap the spoke with the the spoke wrench and make sure all the spokes sound the same. It will take a few rides to seat the new rim so keep an eye on things.
-
No its not that difficult. Here is what works for me, remove the tire lay the rim on its side,scince its cracked try to align the crack hold it in place with vise grips. With a straight egde( a piece of steel flat stock from the hardware) lay and
it over the hub make sure it hangs over each side of the rim. Measure the space between the straight edge and the lip of the rim.Write it down.probably put the crack at 12 o'clock take your measurements at 9 and 3 o'clock.
Becuase we are budget minded on this job getting the spokes out are going to be the hardest part.If you can affrod it go buy one of those thick stubby spoke wrenches.Loosen all the nipples and begin removing the spokes make a drawing of which spoke starts first after the valve stem.There will be different lenghts of spokes so include this in your drawing
Replace the spokes on your new wheel start with that index one at the valve core,slowly tighten them by criss crossing as they get snug check your measurement,final tightening should give you the same space at four points 12-6o'clock and 9-3 o'clock.Mount the rim without the tire on the bike,tape a pointer (pencil) to the fork or swing arm spin the rim for final trueing if needed,Tightening the spokes on one side or the other will pull the rim in that direction. SOAK THE NIPPLES FOR A COUPLE OF DAYS they can be very stuborn hope this helps
-
Excellent advice gents. Are there many types of rims? Do I just count the spokes and buy the same diameter? Mine only crosses two spokes at a time I think. I dunno, I guess I can go to my local dealer and order one and some spokes. $$$$$$$$$$$!
-
What you have for a rim determines the different types of spokes you have-lefties and righties,inies and outies etc.What sachs said about taping the spokes together is a good idea-I'd never heard of it-but even if you're buying new it would help you keep straight which go where and you could untape and replace one matching one at a time in your hub.
-
What you have for a rim determines the different types of spokes you have-lefties and righties,inies and outies etc.What sachs said about taping the spokes together is a good idea-I'd never heard of it-but even if you're buying new it would help you keep straight which go where and you could untape and replace one matching one at a time in your hub.
Sounds good.
-
Find an NOS rim on Ebay (36 spoke D.I.D.), you'll get it for "peanuts".
-
order one and some spokes
Good call on the new spokes. From what I can tell from the
picture, those spoke nipples look to be rusted solidly onto
the spokes. Even if you were able to get the nipples off
without rounding the shoulders, I'd be hesitant to use them
again. Even as a "mild" rider, 28 year old rusted spokes, no
thanks.
You need a 2.15 X 18" rim with 36 holes for your application.
You can either pick up a new "economy" rim and spoke kit
from Moose, Pro Wheel or Warp 9 ($150) or buy a complete
used wheel assembly off of ebay ($50). Just remember, you
get what you pay for.
dogger
-
I bought a complete wheel and forks for an '89 KDX200 for $50 on ebay, gonna stick 'em on my '83 with the cracked rim and get a better front end at the same time :D
-
Well, I took the easy (read lazy) way out. I just dropped it off at my local bike shop and said "fix this please". I like the idea of just being able to pick it up and slap it on my bike and ride. I sure am getting lazy in my old age! ;D I know, I'm gonna get hosed on the cost but I want it to be right. I have enough junk to work on right now as well so it's better this way. ;)
-
What you have for a rim determines the different types of spokes you have-lefties and righties,inies and outies etc.What sachs said about taping the spokes together is a good idea-I'd never heard of it-but even if you're buying new it would help you keep straight which go where and you could untape and replace one matching one at a time in your hub.
When I replace a wheel, I tape all the spokes where they cross, then just cut them all at the nipple so I don't have to loosen every nipple to get the wheel apart. The spokes and nipples are trash anyway...
Then just set the hub in the center of the new wheel and start replacing spokes. I always do my first four sets ninety degrees apart, that way they hold the wheel and hub in place for the rest.
-
They had to send it to some vintage wheel outfit (I'll get the name later for reference) and have a custom rim and spokes made for it. I guess they have to roll one up special and drill it and then make custom spokes for it and they are gonna lace it up as well. The guy that owns the bike shop I go to has a bunch of vintage bikes and these are the guys he goes to. Gonna cost around $400.00. Oh well, I only have to do it once. I think I'll buy another old stock wheel off of Fleabay and if it's in reasonable shape have it at least re-laced so I have a back up or if I like I can put a paddle on it for the dunes. ;)
-
You can fix that with some scotch tape and elmer's glue. Should hold up on 40 foot jumps but just be careful on the 60 footers.
-
You can fix that with some scotch tape and elmer's glue.
While that likely exceeds factory Maico specs I wouldn't do it on a good RM :P ;)
-
Just wrap balewire around the rim and spray foam insulation in thru one of the holes. That's what some of the local kids do. :o
-
(https://mail.google.com/mail/?account_id=wrangler72257%40gmail.com&ui=2&view=att&th=129676138daef8df&attid=0.1&disp=inline)
Well, this is what I ended up with. $439.00 is what this look costs. ;D
-
hmmmmm, invisible rim? I like ;D
-
hmmmmm, invisible rim? I like ;D
You can't see it? :o
-
I'm looking as hard as I can and I still can't see anything 8)
-
It is sooooo beautiful! :-*
-
??? ??? ??? Ummmmm ??? ??? ???
Is there a photo there?
-
??? ??? ??? Ummmmm ??? ??? ???
Is there a photo there?
Yes. I see it. You guys can't?
-
(http://i.imagehost.org/0585/New_rim.jpg) (http://i.imagehost.org/view/0585/New_rim)
How 'bout this?
(http://i.imagehost.org/t/0585/New_rim.jpg) (http://i.imagehost.org/view/0585/New_rim)
-
Much better... by the way, now I can see the first one. I'm glad that you decided to change it.
-
Very nice!