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Old 07-19-2010, 08:38 PM
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Default 1996 CR250 Showa 47s swap progress

I started a thread a few weeks ago about replacing the 46mm KYB forks on my '96 CR250 with 47mm Showa Twin Chambers from a newer CR. Based on info posted in that thread, I picked up some Showas and triple clamps from a 1998 CR250 on eBay.

Before spending any time/effort rebuilding the Showas, I test fitted them this evening after work.

Finding #1:
The bottom triple clamp and steering stem from the '98 won't work on the '96. The stops on the clamp are different and the lower bearing is smaller on the '98.

Finding #2:
The 47mm Showas will slide right into the stock triple clamps. The top clamp appears to be exactly the same, although it has a different part #. It doesn't seem to be any tighter or looser with either the 46mm or 47mm forks installed. The bottom clamp actually is actually slightly looser with the 47mm forks installed, which seems counter-intuitive. I'm going to try to beg/borrow/steal (J/K about the stealing part) some calipers and measure the exact outer diameters and determine if there is really any difference.

This could be great news for '96 owners who would like to do this swap. Only the bare forks may be needed, instead of the forks and triple clamps.

I bolted the wheel/axle on and it fits perfectly. When I get a chance I'll bolt up the brakes, plastic, etc. Stay tuned for updates.
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Old 07-21-2010, 01:26 PM
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Some pictures would be cool too. Thanks for sharing this information!
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Old 07-21-2010, 09:16 PM
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Man you had me sweating bullets there, since I think I was one of the ones that suggested the swap to you. I have a set off a 2002 in the garage, and a 93 frame (cr500 going into it after about two other things get done). The 2002 and 93 use the same bearing (2491-001) top and bottom. According to bike bandit, the 96 and presumably the 95 which shares the same clamps uses a different bottom bearing and the same top. It is really odd that Honda would make the switch and then switch back.

The stops seem like they will work with the 93 as well. We put these forks on everything including yamahas, and as you say some of the 46's take the 47's. oddly some aftermarket ones didn't as they didnt spring as much I guess.
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Old 07-24-2010, 02:05 PM
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Showas installed:


'96 Bottom triple clamp:


'98 Bottom triple clamp:


---------- Post added at 03:05 PM ---------- Previous post was at 02:57 PM ----------

Quote:
Originally Posted by ossagp View Post
Man you had me sweating bullets there, since I think I was one of the ones that suggested the swap to you. I have a set off a 2002 in the garage, and a 93 frame (cr500 going into it after about two other things get done). The 2002 and 93 use the same bearing (2491-001) top and bottom. According to bike bandit, the 96 and presumably the 95 which shares the same clamps uses a different bottom bearing and the same top. It is really odd that Honda would make the switch and then switch back.

The stops seem like they will work with the 93 as well. We put these forks on everything including yamahas, and as you say some of the 46's take the 47's. oddly some aftermarket ones didn't as they didnt spring as much I guess.
It is odd that Honda would change the lower clamp bearing size, then change it back again. In any case, I got lucky and it looks like this swap is really easy for a '96. Are the steering stops on your '93 frame oriented like the '96 or the '98? (See pictures above). The '96 frame a has a single stop on the frame (at the front of the steering head pipe), whereas I believe the '98 (and probably any aluminum frame CR) has two stops on the frame - one on each side. If so, installing the lower triple clamp from a '97 or newer CR onto an steel framed CR could be problematic.

Last edited by RealityCheck; 07-24-2010 at 02:10 PM.
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Old 07-25-2010, 11:52 AM
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426 yours will swap easier. You will need a different front wheel or hub. You will likely need to weld a small extension to the frame stop.
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Old 08-15-2010, 06:20 PM
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Update: I rebuilt the Showas using a Pivot Works kit, cleaned everthing up, and put in fresh fork oil. Still using the stock spring (probably too light for me). Before getting too carried away with modifications, I wanted to see how the Showas felt in stock form compared to the '96 KYBs (also rebuilt, but with the correct springs for my wieght.

I went to an open practice at one of our local AMA sanctioned tracks and put in 15-20 laps. Frankly, I wasn't expecting much, but I am happy to report that the Showas are a huge improvement over the KYBs. I was absolutely amazed at the difference. They made the whole bike feel more solid.

Total investment:
'98 CR250 forks and triple clamps (not needed) on Ebay: $150 with shipping.
Pivot works rebuild kit: $60
Fork oil: $15

Total: $225 and an hour so worth of work

Probably the best $225 I've ever spent of a motorcycle modification.
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Old 08-16-2010, 01:31 AM
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I have liked the swap on everything I tried it on, including yamahas. I never could have gotten the same improvement on any of them that I did without spending more on the KYB's.
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Old 06-14-2011, 03:04 PM
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I just tried to fit a 95 pro taper top triple clamp on my 96 cr 250 but it didn't fit. From your experience it seems like a 97-98 triple clamp will fit on a 96. Can anyone confirm?
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Old 12-08-2011, 10:28 AM
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Hi guys nice looking bike i have a 95 cr 250 and picked up some 99 forks but they will not fit in the 95 tripple clamps any idears?
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Old 01-08-2012, 09:51 PM
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Quote:
Originally Posted by ianm1982 View Post
Hi guys nice looking bike i have a 95 cr 250 and picked up some 99 forks but they will not fit in the 95 tripple clamps any idears?
The closest fit is the '96 triple clamps. The part numbers for the upper/lower stem bearings are the same for 95 and 96, so the '96 clamps should work on the '95 frame. There are a couple of other things you need to know about this swap. The fork holes in lower clamps will need to be shimmed slightly. A double layer of aluminum from a Dr. Pepper can works perfectly. Also, the axle spacing is a little different. I used a '98 axle with the '96 spacer + a washer. The best way to determine the thickness of the washer is to align the forks like you normally would (i.e., tighten things progressively, compressing the front suspension between each round of tightening), but leaving the left axle clamp nuts and axle nut loose. This will allow the forks to fall into their "natural" position. If you grab the spacer, you'll note that it moves laterally slightly. It shouldn't. Insert a feeler guage between the axle spacer and the fork leg to determine the thickness of the washer you will need.

Shimming the clamps and getting the axle spacing correct is very important. If you don't you'll wear out the fork bushings very quickly and the forks will be harsh due to binding. You'll know it's right when the brake rotor is centered in the caliper and the axle nut is flush with the end of the axle when tightened.
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