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Steering stops: CRF inverted fork conversion

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I'll be installing the set of 2006 CRF250R forks on my XR400 this weekend. I will post a photo pictorial of the job when it is done.

So far here is what I have:

Complete brand new 2006 CRF250R front end--the entire assembly, forks wheel, brake, etc.

Emig Racing conversion stem and upper shim.

New bearings and seals, etc.

I have milled off the steering stops and front number plate pin off the lower clamp. All I need to do is press in the stem and install the lower bearing.

The only big question: STEERING STOPS. Can a few of you guys post some pictures of the steering stops you have installed? Most seem to drill and tap the lower clamp and install bolts. Some weld tabs to the clamp, one even drilled, tapped and installed a scews in to the frame stops.

I would like to see what you guys have done and your comments on how it worked. Details would be great, i.e. size of bolts, what material you are using, etc.

Thanks in advance!

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Hi,

I recently undertook this 2006 CRF USD fork conversion too. EPIC result too! I went the drill, tap & bolt route, as it gives the capacity to move the bolts 'in & out' to give you the maximum steering lock.

I'll try and post some piccys in the near future.

Congratz on taking the leap, it makes the XR the bike it always should have been.

Regards, Nick.

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Rockjockey, thanks a ton! I'll work on it tonight.

Dont drill just yet, make sure your stops will contact the frame in the right (stock) locations. Picture #3SteeringStop4.jpg

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I got mine from a guy in Abilene whos brother was involved in a FMX mishap where his CRF250 got totaled (broke the frame and engine cases) and he was hospitalized. The brother was parting the bike out to help offset some of the hospital costs. I've got about $600.00 in the conversion. Then I sold the stock parts to get a little of that back.

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Steering stops completed last night--it only took about 30 minutes to do. Fit, mark and center punch, use the drill press, and tap. Funny, I thought this would be the hardest part of the job.

You are right, the stops need to be angled slightly for the head of the allen bolt to contact the stop evenly. I took some pictures of this and it looks just like yours, although mine may be slightly higher on the triple clamp (sightly above the casting line).

xArmy--I bought an entire brand new front end from a 2006 CRF250 (everything including the wheel/tire, brakes, fender) for $700 shipped to my door, from a guy who built a race bike. While this may sound expensive, $85 of this was shipping and to buy the forks, the clamps, the wheel, the brakes individually on eBay, not to mention all the other bolts guards, and fixtures, the complete assembly is a smoking deal.

The Emig stem and shim were $180. I am thinking about buying another stem and seeing if a machine shop will take the stock CRF stem and turn it down into a replica.

I'll probably have right at $1000 into the whole conversion by the time I am done. Again, it seems expensive, but considering the time I could have spent spent gathering up all the parts individually, and having a machine shop make the stem, of which I could find none who really wanted to for a reasonable price (more than once I heard, "We do not reverse engineer things, bring your blue prints and we'll talk."), this way is pretty much a direct bolt on--and it is all brand new.

If I like the handling of the new set up, I'll probably buy BRP clamps and have the steering stops built into the lower clamp by LT-Racing in Bremerton, WA.

I'll try to find some time to finish it all up on Saturday.

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Way to go AHRMA. I agree it is much better to make a package deal like AHRMA and I did, as you will need the front wheel,brakes,triples, stem,etc. I read on here somewhere that the XR caliper would bolt up to the CRF forks but this was not the case for me (bolt spacing was not the same). XARMY keep your feelers out and the right deal will come to you eventually just don't rush it. I was going to purchase a set of XR650R forks as the big Kayaba's work extremely well too, then this deal showed up for $400 (actually the ad said "Parting out make offers on what you need"). I called the # and offered 4 bills for the whole front end, he agreed and showed up at the next cross country race pushing everything including bars,grips etc. over to my truck to get the cash (it was funny looking to say the least). I put $200 in getting them re-valved for my intended use.

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When I did mine over the winter, I pieced it together off of ebay. I also got some race tech gold valves for the forks. I have to say the inverted forks on my bike have been by far the best mod I have done. I had the stock forks resprung and I revalve them myself along with a fork brace, and they can't hold a candle to the forks I have now.

As for my steering stops even though you have yours finished, I opted to go with welding on some stops I machined. I figured I wouldnt need to have them adjustable if I machined them just enough so the bolts on the lower clamp didn't contact the tank.

Bike 1

Bike 2

Bike 3

Steering stop 1

Steering stop 2

FYI, is you are going to keep the stock headlight, you will want to reuse the stock XR front brake line/caliper/master cylinder it is about 5 inches longer the the CR/CRF set up and will bolt right up without a problem.

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Well, it is done--at least 98% of it. I still need to mount the front number plate (not here yet), Install the A-loop kit (not here yet either) and decide on what to do with my steering stop mistake.

Here are some pictures. I will post a full photopictorial story when I get a little time.

I have ridden the bike for about an hour--it was just a quick ride, mostly on gravel, I brought no tools for tuning. It does not seem to have any flaws in handling or any funny changes in geometry. Oddly it seem to have a little more oversteer, which I consider a good thing...however I cannot explain it since the fors have 1.4 inches more travel, unless I have the forks raised so high and the stroke is deeper with the CRF fork (the reason you need to use the CRF fender as opposed to the XR fender).

The biggest thing is that the front end is much stiffer from a flex standpoint. I cannot believe how flimsy the stock front forks really are and you cannot appreciate this until you ride two XR400's back to back (I brought one of my other ones to compare).

Additionally, the repositioned bars open the pilot area greatly and it feels like a modern bike, not the old XR with the low bars sitting in your lap.

The only aggressive thing I hit was a set of whoops. The CRF front end soaked them up like the true MX forks that they are :thumbsup: , while I couldn't even attack them with the stock forks (which have .43 kg/mm springs in them0>

The only complaint I have is reduced steering lock, which I can fix a number of ways. Aside from that this was extremely easy project (pretty much bolt on) aside from my steering stop mistake (more on that later).

Here a picture of the candidate before the conversion

http://members.aol.com/vintageracer/usd1.jpg

Here's a picture of what I thought was a sano steering stop...

http://members.aol.com/vintageracer/usd3.jpg

This is a picture of the clamp just before I had the stem and new beraing pressed inn/onto it.

http://members.aol.com/vintageracer/usd4.jpg

A picture of the top clamp, the Apprlied standard height Fat bar mounts and the top of the Emig Stem.

http://members.aol.com/vintageracer/usd5.jpg

Here's a picture of the collossal mistake in judgment. The allen head bolt barely touches the frame steering stop. Horror of Horrors. I can't believe I was off so far on this. I have not yet quite decided what to do about this as my A-Loop kit has not yet arrived. The big issue is that there is a reduced steering lock with the stock tank (bolts of lower triple clamp touch tank if steering stop is not quite long, thereby reducing steering lock) that I hope is eliminated with the A-Loop kit (more clearance). Otherwise I will pitch the stock CRF lower triple clamp and use an Applied or BRP which clamp in front as opposed to the rear.

http://members.aol.com/vintageracer/usd6.jpg

Modified CRF Fender.

http://members.aol.com/vintageracer/usd7.jpg

Here's the bike with the forks installed. I went ridinag about 30 minutes after this.

http://members.aol.com/vintageracer/usd2.jpg

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Suggestions to fix you steering stop. What if you use a regular head bolt instead of the allen or weld a washer on the bolt head.

Looks like a minor problem, nice job overall.

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Nice job AHRMA the ALoop will provide more turning radius as the tank is slimmer (more clearance). If you add two flat washers to the rear mounting bolts on the CRF fender on top of the fender it will provide more clearance for the downtube. Looks like the bolt head would fix the steering stop contact issue. I use the Cycra half vented front number plate as it provides ventilation for the oil cooler. TT has a killer deal on these. What kind or number plate is that on your before picture? Dont forget to add seal savers or mudskins to these as the Showa forks are prone to leakage with excessive dirt/mud build-up. :thumbsup::ride:

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Well, it is done--at least 98% of it. I still need to mount the front number plate (not here yet), Install the A-loop kit (not here yet either) and decide on what to do with my steering stop mistake.

Here are some pictures. I will post a full photopictorial story when I get a little time.

I have ridden the bike for about an hour--it was just a quick ride, mostly on gravel, I brought no tools for tuning. It does not seem to have any flaws in handling or any funny changes in geometry. Oddly it seem to have a little more oversteer, which I consider a good thing...however I cannot explain it since the fors have 1.4 inches more travel, unless I have the forks raised so high and the stroke is deeper with the CRF fork (the reason you need to use the CRF fender as opposed to the XR fender).

The biggest thing is that the front end is much stiffer from a flex standpoint. I cannot believe how flimsy the stock front forks really are and you cannot appreciate this until you ride two XR400's back to back (I brought one of my other ones to compare).

Additionally, the repositioned bars open the pilot area greatly and it feels like a modern bike, not the old XR with the low bars sitting in your lap.

The only aggressive thing I hit was a set of whoops. The CRF front end soaked them up like the true MX forks that they are :thumbsup: , while I couldn't even attack them with the stock forks (which have .43 kg/mm springs in them0>

The only complaint I have is reduced steering lock, which I can fix a number of ways. Aside from that this was extremely easy project (pretty much bolt on) aside from my steering stop mistake (more on that later).

Here a picture of the candidate before the conversion

http://members.aol.com/vintageracer/usd1.jpg

Here's a picture of what I thought was a sano steering stop...

http://members.aol.com/vintageracer/usd3.jpg

This is a picture of the clamp just before I had the stem and new beraing pressed inn/onto it.

http://members.aol.com/vintageracer/usd4.jpg

A picture of the top clamp, the Apprlied standard height Fat bar mounts and the top of the Emig Stem.

http://members.aol.com/vintageracer/usd5.jpg

Here's a picture of the collossal mistake in judgment. The allen head bolt barely touches the frame steering stop. Horror of Horrors. I can't believe I was off so far on this. I have not yet quite decided what to do about this as my A-Loop kit has not yet arrived. The big issue is that there is a reduced steering lock with the stock tank (bolts of lower triple clamp touch tank if steering stop is not quite long, thereby reducing steering lock) that I hope is eliminated with the A-Loop kit (more clearance). Otherwise I will pitch the stock CRF lower triple clamp and use an Applied or BRP which clamp in front as opposed to the rear.

http://members.aol.com/vintageracer/usd6.jpg

Modified CRF Fender.

http://members.aol.com/vintageracer/usd7.jpg

Here's the bike with the forks installed. I went ridinag about 30 minutes after this.

http://members.aol.com/vintageracer/usd2.jpg

AH that is an awesome job!!!!!!!!!!!!!!!!

The gold forks really look sensational on the XR400.

Now is that a stock XR400 or CRF front fender?

Did you think you have to trim the fender at all?

Also - how do the spring rates feel? Are they simply waaaay off or not far off?

Are they too soft or still to heavy?

Brakes - how do they feel?

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AH that is an awesome job!!!!!!!!!!!!!!!!

The gold forks really look sensational on the XR400.

Now is that a stock XR400 or CRF front fender?

Did you think you have to trim the fender at all?

Also - how do the spring rates feel? Are they simply waaaay off or not far off?

Are they too soft or still to heavy?

Brakes - how do they feel?

The fender is the CRF fender. The rear two bolts need two flat washers each to clear the frame and it also needs about 3 inces cut from the rear of the fender.

I am not sure the XR fender will work. The Acerbis XR fender that was on the bike has a ridge between the mounting bolts that is about an inch tall. The CRF fender is flat. I raised the forks as far as I could go to kepp the geometry as close to stock a possible (and I hate motercycles that do not turn sharply). I think that the tire would have hit the ridge under full compression.

I have not taken it to the MX track, but the spring rates seem to be right on for aggressive trail riding, whereas even the .43 kg/mm equipped stock forks were not stiff enough. I am a pretty aggressive rider and will probably put .47 kg/mm springs in the CRF forks as opposed to the .45s kg/mm. The thing is that it is not so much the spring rate that is better on the CRF forks, it is the damping characteristcs which are both speed and position sensitive. The control when compared to the stock XR fork is unbelievable. So, in any case, the stock CRF fork springs are spot on for general riding--an unbelievable improvement. The CRF forks are better everywhere from the choppy washboard to the big hit.

The brakes are another bonus. While I am positive that the CRF master cylinder and the XR master cylinder are identical (even the casting marks and numbers are the same), the CRF brake is stronger, probably due to the larger CRF rotor (240mm vs.260mm) and the shorter brake hose. It is like buying an aftermaket oversize rotor and mount, but it is all OEM Honda with no adapter bracket for the caliper!

The only issue I have with any part the conversion is the reduced steering lock due to the lower triple clamp fork clamp bolt position, but this can be alleviated by the A-Loop kit or the correct aftermarket triple clamp.

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What kind or number plate is that on your before picture? :thumbsup::ride:

The front numberplate is a UFO vented plate for a 1995-1999 Honda CR125/250. White Brothers part number 51-3020.

You guys are going to laugh you ass off at this...

As you know I have been complaining about the reduced steering lock because the lower triple clamp hits the stock tank. My A-Loop kit is not yet here (supposed to be next week) so I was in the garage this evening looking at my three XR400s comparing the forks, the tank, and the triple clamps.

One is the conversion bike, one is 100% stock (a 2002 with only 65 miles on it), and one is my dual sport bike with a 3.8 gallon Clarke tank.

The funny thing was that when I was looking at the Clarke tank equipped dual sport bike it seemed like there was a lot more clearance for the forks than the stock unit--the Clarke tank is designed a little differently. About 5 minutes later I had the Clarke tank swapped onto the bike with the inverted forks.

Wonder of wonders, there is a mile of space and clearance with the inverted forks. I repeat, there are ZERO clearance problems when you use a Clarke tank. You can set the forks up to turn even tighter than the stock set and you will have NO CLEARANCE PROBLEMS!!

So...I'll be you know what I am looking for now: A complete CRF450X front end for my dual sport XR400!!!

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