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1982/83 43mm forks on a 1980 CR250 Options?
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Author:  FlyArmy [ Sun Jul 04, 2010 9:52 am ]
Post subject:  1982/83 43mm forks on a 1980 CR250 Options?
Option one: I have thought larger forks on my 1980 CR250 would be a great modification and I am wondering what I would be getting myself into before I do it. What is required to change the front ends besides the wheel, brake, forks and triples? I understand the steer stem does not works. What is the easiest way to do this modification?

Another option: I do have a set of 38mm/12 inch travel Simons forks and CR250 front brake and wheel that I recently restored (re-chromed tubes and sent to Thor), but they do not have the triple clamps for a Honda. I had them on a 1980 RM125T with the stock 38mm triples. I am almost in the same situation as the 37mm triples will not take the Simons forks and I need a 38mm triple clamp with laid back handle bar clamp to handle the 37 inch length of the tubes without making a chopper. Any suggestions on what year Honda to look for that had 38mm tubes and rear mounted bars?

Thanks in advance,
Mike

1980 CR250 and 1980 CR125
Author:  whymee [ Sun Jul 04, 2010 5:26 pm ]
Post subject:  Re: 1982/83 43mm forks on a 1980 CR250 Options?
Mike,

I am in the process of restoring / modding a 79 CR250. I assume the front end is the same for 78/9 & 80 models...

I installed a front end from a 83 CR250. Fairly simple process. Use the complete front end including tripples & bearings. I had to make a spacer under the spanner nut 'cause the head tube on the 79 is shorter than the 83. As a matter of fact the spacer is another spanner nut that I turned out the threads on my lathe.

Simple, IMHO.

*** DISCLAIMER ***

I have not rode the machine yet. Waiting on white 1980 side panels (VMX.com) & fuel tank back from body shop. Mine is all white with a black motor.

Questions? Call me...

Hope this helps

Stan
304-265-0670
Author:  Dos Rios [ Mon Jul 05, 2010 12:01 pm ]
Post subject:  Re: 1982/83 43mm forks on a 1980 CR250 Options?
The 83 CR480 front end will rake out your bike a few degrees and wll effect corning somewhat. I installed a new set of CR480 billet aluminum triple clamps and one piece bar clamps on my 79 CR250. They bring the rake back in on the 43mm fork set up. They look really cool but are somewhat pricey at 425 bucks. Terry
Author:  FlyArmy [ Mon Jul 05, 2010 8:19 pm ]
Post subject:  Re: 1982/83 43mm forks on a 1980 CR250 Options?
Thanks for the replys so far. Great discussion going on here. I think the 1982 frame might be a little closer to the 1980 than the 1983? Here is what I found from the Cycle World articles on this site and the numbers are degrees of angle and inches:

rake trail
1980 28.25 4.5

1982 27.00 4.2

1983 26.00 3.9

If the triples and fork length from the top to the axle center are held constant, I guess the 1982 frame is the closest to the 1980 frame in rake and trail? The 1983 has less of an angle and rake, which I think would result in quicker steering. Does anyone know if the triple clamps are the same? Has anyone else experienced steering issues by going to the larger forks? Please offer any input to what I have found above.

The aluminum triple clamps sound great but the cost may out weigh the benefit for me? Who makes them and are they made to the 1978-80 CR250 specifications?

Thanks,
Mike
Author:  Dos Rios [ Thu Jul 08, 2010 8:26 pm ]
Post subject:  Re: 1982/83 43mm forks on a 1980 CR250 Options?
Maico's only makes them and they are for the 78,79,80 CR250's.
Author:  tater [ Thu Jul 08, 2010 10:38 pm ]
Post subject:  Re: 1982/83 43mm forks on a 1980 CR250 Options?
i installed a set of 83 cr 480 forks (43mm) on my 79 cr 250,they work great. i was told by a arm chair mechanic that rake angles are determined at the frame and off sets at the triple clamps also 83 cr 125 forks are 38 mm it should be easy conversion pm me if you have questions? terry
Author:  FlyArmy [ Fri Jul 30, 2010 2:22 pm ]
Post subject:  Re: 1982/83 43mm forks on a 1980 CR250 Options?
I installed a 1980 CR250 steer stem and bearings in a set of 1982 CR480 triple clamps and it fit perfect. No modifications required and a very straight forward modification. I will now have the ability to use the larger 43mm forks on my 1980 CR250 or CR125 with the DLS front wheel.

Has anyone used the Race Tech emulators on their 43mm forks? Were they easy to install and did they really work?
Mike
Author:  aja72 [ Mon Aug 09, 2010 1:48 am ]
Post subject:  Re: 1982/83 43mm forks on a 1980 CR250 Options?
Instruction of the front forks installation.

1> Put bike on a stand that will enable front tire to be off the ground.
2> Install forks in triple clamps, ensure that both forks are the same height in the triple clamps.
3> Make sure that the bleed screws are towards the front, this will make bleeding the air from your forks easier.
4> Tighten each bolt in the top clamps to 280 inlbs.
5> Tighten the lower clamp pinch bolts to 220 inlbs.
6> Install front wheel assembly.
7> Before tightening any pinch bolts go ahead and fully tighten the axel nut.
Author:  montywa [ Mon Aug 30, 2010 1:51 pm ]
Post subject:  Re: 1982/83 43mm forks on a 1980 CR250 Options?
I run 82' CR480 forks on my 80' cr250. I bought the racetech springs and emulators for them. I have never been impressed with the forks. Not to mention the handle bars always feel like they are in my lap, i get a lot of head shake at speed and after landing off a jump. I never feel comfortable on the bike. I am going to swap in some 43mm YZ forks to see how they handle. If anyone knows how to move the bars forward with the CR480 clamps i would love to know.
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