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Discussion Starter #1
has anyone done a cr 500 swap into there if so what would i need to do to make it happen or is it worth just building a 330 esr non pv engine??
 

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i have seen some done, that look very good. basically you just need to weld up some new motor mounts, and figure out a way to deal with the massive amounts of vibration. your going to want to use some rubber bushings at the engine mounts if you can to calm things down a bit, and deffinatly an anti vibe stem. also make sure you start out with a strong frame, and use loctite on everything. if your looking for a 500 build though why not try a LT 500? its already counterbalanced.
 

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i have seen some done, that look very good. basically you just need to weld up some new motor mounts, and figure out a way to deal with the massive amounts of vibration. your going to want to use some rubber bushings at the engine mounts if you can to calm things down a bit, and deffinatly an anti vibe stem. also make sure you start out with a strong frame, and use loctite on everything. if your looking for a 500 build though why not try a LT 500? its already counterbalanced.
Or a Saber?

From the people I have talked to, the CR 500 swaps are almost un-rideable. MAC Racing did one years back, it was a drag bike but they could not get rid of the terrible vibration of the motor. They did the rubber mounts, stem, everything. They even tried an aluminum frame before giving up on the project. I was told that the foot pegs vibrated so bad that it actually sent a chill up your spine!

MAC then tried a hybrid (TRX 250R bottom end, and a CR 500 top), but I don't think it ever worked out to anything great. Here is an article nontheless:

http://www.atvsource.com/articles/product_..._mac_racing.htm
 

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whatup,
i was wantin to do this setup for this dune season but pushed it back till next. i'm actually doin a cr500 cylinder swap onto the 250 bottom end with an 8mm stroker. that way the gearing is setup like a 250r and its counterbalanced which will get rid of the gnarly vibrations. not to mention it's ready to bolt in to the stock frame. phoenix custom out of az is doin my motor work. the dude's a wizard. mac racing did a setup like this. they didn't just swap motors they swapped cylinders. check it at:
http://images.google.com/imgres?imgurl=htt...ficial%26sa%3DN
let me know what you wanna do with this build as i'm very interested myself.

has anyone done a cr 500 swap into there if so what would i need to do to make it happen or is it worth just building a 330 esr non pv engine??
 

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Discussion Starter #5
alright because i damaged my cases the other night as i was pressing them together i hope that i can repair them and if not then im going to get new ones does anyone know the stock horsepower rating of a cr 500 because i would still like to build my engine but i dont know what would be better im guessing sticking with a counterbalanced motor and why does it vibe so bad on the quad frame and not so bad on the dirtbike frame is it just design??
 

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alot of it is in the frame design, I know guys who put cr500 motors in atc250r and they said the vibration isn't too noticable. 84-87 kawaski tecate 3's used basically a kx250 motor, no counterbalancer, the vibration was barely noticable, I didn't realize it didn't have a counter balancer untill I redid the clutch. For some reason the quad frames magnify vibration and running the swingarm bolt thought the motor acts as a tunig fork, but it doesn't in the bike??
 

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I dont think its worth putting in a 500 motor. You can make 60Hp easily out of a 370R
 

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ya a 350 powervalve will be your best bet, if your really hellbent on a 500 with loads of power you could maby look at a saber, but i think that those are more for just drag racing
 

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If you want to go big, just build your R motor big. I'd say a 350, 370, or one of the new saber, sphinx, etc. It will run good, not vibrate, look better, be easier, pipes will fit, intake will fit, etc.
 

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The biggest draw back to building a bigger TRX based engine is the transmission gears. The old 86 model engines were bad about busting gears but the ratios of those gears were perfect for the big bore cylinders.
The 88 or 89 transmissions were the best but you can even bust a gear in those, it just a toss up if you have one thats lasted a good while.
What I have on my mind after working on so many 250Rs would be a CR500 based engine with an added counterbalancer in the mix.
Only way this could happen would be to design billet cases with mounts in the same places as the TRX engine but all the machining on the inside like the CR500 & then include the balancer.
With a balanced crank, rod & piston & then the balancer that should take care of a bunch of vibs. The CR500 transmission should be able to handle just about any amount of HP we could throw at it & last for a good while as well.
The LT500 Suzuki is counterbalanced some but not as much as needed.
The CR500 engine even in the dirt bike frame the vibs are there as well, been many frames cracked & repaired.
Neil
 

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The biggest draw back to building a bigger TRX based engine is the transmission gears. The old 86 model engines were bad about busting gears but the ratios of those gears were perfect for the big bore cylinders.
The 88 or 89 transmissions were the best but you can even bust a gear in those, it just a toss up if you have one thats lasted a good while.
What I have on my mind after working on so many 250Rs would be a CR500 based engine with an added counterbalancer in the mix.
Only way this could happen would be to design billet cases with mounts in the same places as the TRX engine but all the machining on the inside like the CR500 & then include the balancer.
With a balanced crank, rod & piston & then the balancer that should take care of a bunch of vibs. The CR500 transmission should be able to handle just about any amount of HP we could throw at it & last for a good while as well.
The LT500 Suzuki is counterbalanced some but not as much as needed.
The CR500 engine even in the dirt bike frame the vibs are there as well, been many frames cracked & repaired.
Neil
 

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Don't bother with the 500 conversion. It's not worth the hassle. Check out cpindinc.com and go up to products and click on the 250r portion. You will see there are now 3 cylinders available now with multitudes of CC options. I am very interested in the Puma 85x76 bore stroke combo. It runs a CR 500 reed cage, and it appears to have a piston coming real soon that you can use a longer rod than the 250 rod to make a better rod/stroke ratio. With the right pipe, I think this will be a killer setup. Better than the Saber in my opinion. Bigger isn't always better.

You can make a big bore 250r last but it's not something you can slap a bunch of parts at and have it live. At minimum on the tranny, you need 2,3,4th gears on both sides of the shaft to be fresh. Best case would be a Yukon gear set on one side (set is only on the countershaft I believe) and new 2,3,4 Honda gears on the other side. This will set you back about 5-600.00. Anything bigger than a 370 will need an 8 plate clutch setup if shifting with the clutch (non override) and stiffer clutch springs. The setup I'm talking about above really needs the crank balanced with the bigger piston, so this is an additional couple hundred bucks. Custom pipe will need to be made since most pipes for the 250 are really made for a 250. This will run a guy about $500.00.

I could go on, but you can see where I'm getting at. Sphinx cylinder will be the least expensive, then comes the Puma, and the biggest dollars spend to get it running to it's full capability is the Saber. I belive even though a bit pricey, the biggest bang for the buck will be the Puma.

These cylinders will reserect our beloved 250's and get us on pace with the Banshees now.
 

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The biggest draw back to building a bigger TRX based engine is the transmission gears. The old 86 model engines were bad about busting gears but the ratios of those gears were perfect for the big bore cylinders.
The 88 or 89 transmissions were the best but you can even bust a gear in those, it just a toss up if you have one thats lasted a good while.
What I have on my mind after working on so many 250Rs would be a CR500 based engine with an added counterbalancer in the mix.
Only way this could happen would be to design billet cases with mounts in the same places as the TRX engine but all the machining on the inside like the CR500 & then include the balancer.
With a balanced crank, rod & piston & then the balancer that should take care of a bunch of vibs. The CR500 transmission should be able to handle just about any amount of HP we could throw at it & last for a good while as well.
The LT500 Suzuki is counterbalanced some but not as much as needed.
The CR500 engine even in the dirt bike frame the vibs are there as well, been many frames cracked & repaired.
Neil
So how much $$$ and when are you going to get started? LOL
 

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The biggest draw back to building a bigger TRX based engine is the transmission gears. The old 86 model engines were bad about busting gears but the ratios of those gears were perfect for the big bore cylinders.
The 88 or 89 transmissions were the best but you can even bust a gear in those, it just a toss up if you have one thats lasted a good while.
What I have on my mind after working on so many 250Rs would be a CR500 based engine with an added counterbalancer in the mix.
Only way this could happen would be to design billet cases with mounts in the same places as the TRX engine but all the machining on the inside like the CR500 & then include the balancer.
With a balanced crank, rod & piston & then the balancer that should take care of a bunch of vibs. The CR500 transmission should be able to handle just about any amount of HP we could throw at it & last for a good while as well.
The LT500 Suzuki is counterbalanced some but not as much as needed.
The CR500 engine even in the dirt bike frame the vibs are there as well, been many frames cracked & repaired.
Neil
cant you buy aftermarket gears
 

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i saw yukon 250r gears for like $350 in the back of dirtwheels last month.

I saw go for the LT500 swap, yeah yeah the 250r can make 60hp, the LT can make 85+ :blink:

I have one in a 92LT250r frame, it would be much much better if this motor was in a TRX. I have a 88 roller and another 500 motor Im getting ready to have Rx'd.

but for now I still prefer to ride my TRX250R as the daily driver :)
 

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i saw yukon 250r gears for like 0 in the back of dirtwheels last month.

I saw go for the LT500 swap, yeah yeah the 250r can make 60hp, the LT can make 85+ :blink:

I have one in a 92LT250r frame, it would be much much better if this motor was in a TRX. I have a 88 roller and another 500 motor Im getting ready to have Rx'd.

but for now I still prefer to ride my TRX250R as the daily driver :)
lol duncan sells those gears for 600, not a suprise tho coming from duncan
 

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Or a Saber?

From the people I have talked to, the CR 500 swaps are almost un-rideable. MAC Racing did one years back, it was a drag bike but they could not get rid of the terrible vibration of the motor. They did the rubber mounts, stem, everything. They even tried an aluminum frame before giving up on the project. I was told that the foot pegs vibrated so bad that it actually sent a chill up your spine!

MAC then tried a hybrid (TRX 250R bottom end, and a CR 500 top), but I don't think it ever worked out to anything great. Here is an article nontheless:

http://www.atvsource.com/articles/product_..._mac_racing.htm
YEP!!!!! I built one and it was the biggest piece of junk. What a waste of a good frame. STICK WITH WHAT WORKS. Dont waste your money on it.. Good luck if you try it.
 

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i really want to do a cr500 transplant into my 250r also. it is way cheaper than getting a aftermarket cylinder, is more powerful, and reliable. you can get 70hp+ easy with a decent pipe and a port job on the cr500 motor. the only downside is the viberation, but i hope to dampen them by rubber mounts and maybe putting silicone in the handlebars. an aftermarket cylinder is about 1200 and you need to beef up the clutch get a bigger carb and it will stress the internals of the motor. a complete cr500 motor in good condition can be had for under a grand and then you can sell off the old 250 motor becasue you wont need it anymore. the cr500 will be a little more work but it seems like a better option. let me know if im wrong...
 

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i really want to do a cr500 transplant into my 250r also. it is way cheaper than getting a aftermarket cylinder, is more powerful, and reliable. you can get 70hp+ easy with a decent pipe and a port job on the cr500 motor. the only downside is the viberation, but i hope to dampen them by rubber mounts and maybe putting silicone in the handlebars. an aftermarket cylinder is about 1200 and you need to beef up the clutch get a bigger carb and it will stress the internals of the motor. a complete cr500 motor in good condition can be had for under a grand and then you can sell off the old 250 motor becasue you wont need the money. the cr500 will be a little more work but it seems like a better option. let me know if im wrong...
Now that the new CP cylinders are coming out, you can pick up a used Pro-X for cheap (under and around $500) and come pretty damn close to 70 hp with and it will be just as reliable if not more with a good bottom end, pipe, and carb. Plus you wouldn't have to modify your frame. JMO I guess.
 
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