CR250R Conversion to ATCR250R

**max** · 03-09-2006, 01:41 PM

You must be crazy. You will FINALLY have a trike. A sweet one to say the least. Yeah, sell it,..... and be a trikeless turd again. If you plan on offing it atleast have something on hand before so. By the way, very nice project. I wasnt aware of your mechanical capabilities. You definately know what your doing here guy!! We will see ya soon here. April 29th baby!!!! goble goble.

**sp1tekiller** · 03-09-2006, 03:06 PM

Those CRF450's like to eat intake valves. Make sure you are handy at tearing apart a thumper if you go that route.

**3Razors** · 03-09-2006, 03:57 PM

Originally Posted by sp1tekiller

Those CRF450's like to eat intake valves. Make sure you are handy at tearing apart a thumper if you go that route.

I also here that you are supposed to do a topend like every 30 hours or something on those?! I mean come on, whats the point of a four stroke if you have to give it even more $$$ and maintanence than a 2 stroke.

**Aussieboy1** · 03-09-2006, 04:15 PM

There used to be a company is Australia back in the day based in Brisbane, which did a kit to make a 2 wheeler into a trike. But they didnt do the front end. I raced against a couple myself on my 250r's. One is still around in my home town ( Mildura) It was a 84 KX 250, it looked a little funny but went really well..

**atctim** · 03-09-2006, 04:58 PM

Originally Posted by sp1tekiller

Those CRF450's like to eat intake valves. Make sure you are handy at tearing apart a thumper if you go that route.

From my experience and research, only the CRF250's have valve issues, the 450's are fine.

BTW - Awesome project!!!!!

**sp1tekiller** · 03-09-2006, 06:28 PM

The 450 has them to, most significantly the '02 - '03.

**SpeedBump** · 03-09-2006, 06:43 PM

Originally Posted by sp1tekiller

Those CRF450's like to eat intake valves. Make sure you are handy at tearing apart a thumper if you go that route.

I have heard of that issue as well. I am not so sure it actually happens all that much, but in the even it does, I can replace them with the TRX450R valves and topend parts for a bit less performance, but alot more durability.

BTW, I'm handy at tearing apart Thumpers AND 2Smokes!!!

Again, thanks for the words of encouragement.

Max, gobble, gobble!!! Don't worry bout me and having a trike. I'll be fine. I am working on gettin me a nice 350X for a woods/trail/backup machine. I got time...chilllllll boi!!!

3Razors, After I get this all done, I will see how much $$$$ will be involved in it. The guy who is building these for me...with me providing all the info....is NOT getting things accomplished as fast as I would have expected. He is very busy with his Job, and family....I am not busting his ass about this....We all have priorities. My point to all of this...I will need to find somebody else to build them for me. I have another friend who is in the process of starting his own shop, but he is kinda tied up right now with his first major Client. http://www.gradall.com/home.html He should have things settled in and then he may be able to work with me on these side projects. If he doesn't work out. I have a couple more firends involved with machining. I'll keep my options open for sure.

PS, I sent you a PM to talk about $$$$$$

**3leggeddog** · 03-09-2006, 07:16 PM

i don't think a 450 is a good idea.they got too much torqe,and would lift the front wheel too much.thus making it difficult to corner.they also do not spin the tire,or tires as easy,making the frint end plow/push even more.good in theroy,but i think it would hanle like crap.just my opion though,i'll ride whatever you build buddy!!!!!!!!1

**3Razors** · 03-09-2006, 10:49 PM

Sounds good. I think the triple clamps have always been the main thing keeping people from pulling off these projects. If you could have sets ready to ship it would be more of a "slam dunk" for anyone interested.

**toyota200x** · 03-11-2006, 12:45 PM

Originally Posted by 3Razors

You are really onto something... When you think about it a kit would give everyone the option of having "new" 3 wheelers. Not having to worry about discountinued parts or high ebay prices. I know I would like to buy a set of triple clamps.

I was just thinking the other day "where are 3 wheelers going to be in 15 years?" I hope more people and maybe some shops start selling kits. Awesome project.

**OZQUAD44** · 03-11-2006, 03:30 PM

Originally Posted by 3leggeddog

i don't think a 450 is a good idea.they got too much torqe,and would lift the front wheel too much.thus making it difficult to corner.they also do not spin the tire,or tires as easy,making the frint end plow/push even more.good in theroy,but i think it would hanle like crap.just my opion though,i'll ride whatever you build buddy!!!!!!!!1

I'm not too sure I aggree with you 3leggeddog. By that reasoning your suggesting that four strokes don't corner as well as two strokes. Now that MIGHT be true on a weight to weight only argument but on a power delivery argument I think that is not quite right. I can tell you that my Tecate loves to spin its wheels VERY easily and I can also tell you I wish I had my YFZ motor in my Tecate every time I'm trying to negotiate any corner. Smooth power delivery only helps cornering. Yes it gives you more traction, but it also gives you a smoother power delivery. I hope your not suggesting that a CRF450 motor can't spin its wheels? I know my yfz450 spins its wheels when ever i feel like playing.
In no way am I trying to insult you I just don't really aggree with your last post
Cheers

**3leggeddog** · 03-12-2006, 12:00 PM

well i am not implying that a 450 can't spin the tires.i just think with the tractable power,or smoothe power delivery,it will push the fornt more.with more tourqe,or traction,naturally the front end becomes light,causing it to push/plow.

with the 2 stroke power plant it will just spin,rather then hook up,and lift.i use the throttle,and the wheel spin alot when corning.

you may be right,it's just how i see it.

**SpeedBump** · 03-13-2006, 11:21 PM

Got the front brakes nearly finished. This one started out way hard, but looks like it is gonna be one of the easier fabs. Ok, from the start of this project, the plan was to use as many of the CR parts as possible. I wanted the benefits of the newer tech. I was unsure about the front brake assy. I knew I wanted to use it, but couldn't see how it would work. Seemed completely different on the Motorcycle, but once I got into it, wow did it just seem simple. I bolted up the caliper, slipped the wheel with the stock rotor installed and holy crap, they lined up nearly perfect. I looked at it for a while, moved things here and there, checked and rechecked clearances, and was shocked to see it really was nearly perfect AS IS. Nearly isn't good enough so I started thinkin. Thinkin wasn't doing me any good, so I took the two rotors and tossed them down on the workbench and when I did, they landed right on top of each other in such a way as to make to take notice. The smaller diameter 350X rotor was laying under the larger R rotor and the mounting holes in the R rotor kinda looked like they lined up with the cooling grooves machined into the X rotor. I slid them around a bit, and and then grabbed a small rattail file. I gave the gooves a quick file to clean out the paint and a bit of crud and BAM! the two rotors bolted together PERFECT! Now, you may be wondering what good is that, but it gave me an idea. I could just bolt the stocker on the wheel hub, then bolt the R to IT. It also gave me a little bit of offset that was needed to get the wheel/tire lined up in between the forks a bit better. I did it, tried to put it in, and then realized the X rotor was getting in the way from being about 3/4 inch too large. I thought about cutting the center out of the X rotor, but decided NOT to ruin it, and opted for finding some nice aluminum and making an adapter that would be the same as the center section of the X rotor. I only needed it to be about the thickness of a rotor (1/8" or so) but then got to thinkin about that too. I didn't want to make it too weak to hold up to the punishment I was gonna be puttin this thing through. I settled on a piece of 1/4" thick plate aluminum and to make a long story short, cut, ground and knocked it out tonight. I DID mess up a wee bit. I wanted to get the bolt holes lined up differently, but got in a bit of a rush and kinda forgot to re-align them. (weather turning crappy again so wanted to get as much done as I could) It is finished enough to use now, but I will be putting it to the sander and buffing wheel before it gets put together for the final time. Here are a few pics of it mounted up on the forks. Later all.

**SpeedBump** · 03-13-2006, 11:26 PM

Oh ya, BTW, from what I can tell, the R rotor WITH the aluminum adapter plate weighs LESS than the STOCK X rotor. Looking at it in the pics, really makes me upset. I am gonna have to make another one and get the bolts in a triangular pattern, that drives me nuts seeing them like that. If I make a new one, then I can also put in a few well placed holes for a more finished look. Being a smooth solid piece kinda makes it look "cheap"... Can't have that!!!

**Red Rider** · 03-14-2006, 04:27 AM

Originally Posted by SpeedBump

If I make a new one, then I can also put in a few well placed holes for a more finished look. Being a smooth solid piece kinda makes it look "cheap"... Can't have that!!!

I agree. Now I don't have to point that out to you! It's all looking good so far. I'm anxiously awaiting the outcome of this project.

Thread: CR250R Conversion to ATCR250R

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