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View Full Version : CR500 Engine + 250R Frame



Paysts
08-05-2006, 06:06 PM
I would like to put a CR500 engine in to my 85 250R. Is this hard to do? The engine in my 85 250R is toast.

Also, what are some good years for the CR500 engine?

Post away. Thanks.

Louis Mielke
08-05-2006, 09:37 PM
several people here have done it. lotsa work. lotsa welding. unless you're a balls to the walls kinda rider just rebuild your 250 engine. You'll be surpised how well your 250 will run with afresh rebuild.

Yamaha Tri-Moto
08-05-2006, 10:36 PM
Agreed, lots of work. But it would be real fast.

200x Basket
08-05-2006, 10:47 PM
i did it and love it. but it is not a good trials machine

Orangecnty250r
08-06-2006, 12:06 AM
Thats one machine I've always wanted to do...I have to many projects going right now but maybe someday I'll tackle this one...My dream is to have it look like a 100% original 1986 ATC with the 500 motor painted the proper dark silver and Harlans atc 500 factory looking decals on it. Thats a dream machine for sure.......good luck with your project

Aussieduner
08-06-2006, 01:30 AM
i did it and love it. but it is not a good trials machine

I love your 500r its one of my favorite trikes !

Aussie

atcsteve
08-06-2006, 12:31 PM
One major problem is the vibration from the cr 500 motor,what a pain in the butt.They are fast,but my built 250r's will outrun a semi stock cr 500 all day long,with less problems!!There is a reason honda didnt put these in trikes!!

gasmask
08-06-2006, 03:31 PM
do a search of 500r on here and 3wheeler.org. a few people on here has do it. basket and kasey i know for sure. basket show you step by step the process. i bought his first 250r/500 frame and only had one problem. that was 3 yrs ago. i reinforced the frame under the motor and that's all she wrote. no more problems...i believe kasey also has a step by step process. check both site and then make your decission. it's a fun ride but it will hurt you...

KASEY
08-06-2006, 04:27 PM
One major problem is the vibration from the cr 500 motor,what a pain in the butt.They are fast,but my built 250r's will outrun a semi stock cr 500 all day long,with less problems!!There is a reason honda didnt put these in trikes!!


i wish i had a nickel for everytime i saw this,,,,,, DON'T BELIEVE IT FOR A MINUTE!!!!!! OH BY THE WAY STEVE they did have a ATC500R prototype in the works,,, and i would say it might have been on the dealers show room floor in 88 if things were different,,,, :rolleyes: :rolleyes: :rolleyes:

Louis Mielke
08-06-2006, 07:01 PM
One major problem is the vibration from the cr 500 motor,what a pain in the butt.They are fast,but my built 250r's will outrun a semi stock cr 500 all day long,with less problems!!There is a reason honda didnt put these in trikes!!


Dude are you for real? My 500 vibration is barely noticable. Only after riding for several hrs are my hands even slightly sore.

I would be carefull what you say dude. I'm pretty sure you can no longer count the number of people with 500s on these boards with just one hand anymore.

hoser
08-06-2006, 07:53 PM
Here you go 98 hp
http://www.cpindinc.com/products/honda/TRX510R/TRX510R.html#

Billy Golightly
08-06-2006, 09:04 PM
There is only one way in my opinon (take for what its worth:rolleyes:) to do this conversion correctly. Its not using the dirtbike frame like I did, or using the 250R frame. Its to make a whole new one specificly for what your trying to do. No matter how much you mod the 250R frame to fit the 500, or the 500 frame to be a trike, your still trying to change it from one thing to another and it will never be as good as something purpose built. The 250R frame conversions have the potential (although low) for stress and breakage due to the removal of two of the lower frame rail supports. The 500 frame conversions are tall, raked out to far, and wobbly although less likely of a failure...

You have 3 options, pretty much. Take your pick.

Louis Mielke
08-06-2006, 09:59 PM
There is only one way in my opinon (take for what its worth:rolleyes:) to do this conversion correctly. Its not using the dirtbike frame like I did, or using the 250R frame. Its to make a whole new one specificly for what your trying to do. No matter how much you mod the 250R frame to fit the 500, or the 500 frame to be a trike, your still trying to change it from one thing to another and it will never be as good as something purpose built. The 250R frame conversions have the potential (although low) for stress and breakage due to the removal of two of the lower frame rail supports. The 500 frame conversions are tall, raked out to far, and wobbly although less likely of a failure...

You have 3 options, pretty much. Take your pick.


Amen! Now get back to work, who said you could get on the internet? We need that aluminum prototype done!

3Razors
08-06-2006, 09:59 PM
One major problem is the vibration from the cr 500 motor,what a pain in the butt.They are fast,but my built 250r's will outrun a semi stock cr 500 all day long,with less problems!!There is a reason honda didnt put these in trikes!!

Im calling BS on this one. Wrong on both ends buddy. The vibration in a 3 wheeler is very minimal. It will take much more than your 250r with a 310 kit run down even a stock cr500. And as far as reliability?!! The cr500 motor is one of the most well built motors ever! It is stone ax reliable that can take lots of abuse.

Billy Golightly
08-06-2006, 10:13 PM
Amen! Now get back to work, who said you could get on the internet? We need that aluminum prototype done!

Aluminum is in the shop and am jigging up the welding table


Billy=:crazy:

Louis Mielke
08-06-2006, 11:07 PM
blah what really sucks is i did some work on my motor today, got the jug off finally. Looks like i overheated it bad enough to seize it for a few seconds. The cylinder looks like it may be ok with hone but the piston is trashed.

I shoulda just put it up for the week. oh well. Learn the hard way don't I?

I'm at the 2mm over weisco now. does anyone know if anyone else makes a piston bigger? i think I could get by with a new 2mm but I'd rather go to the next size. blah.

gasmask
08-06-2006, 11:28 PM
try TJ Parts X-Press 800.256.9309. keep calling and most of the time you will always talk to someone different. they sell wiseco and pro-x pistons etc. price range from $89.00 to 108.00 shipped. each person has a different price. now i only buy the pro-x pistons.

atcsteve
08-07-2006, 05:06 PM
Im calling BS on this one. Wrong on both ends buddy. The vibration in a 3 wheeler is very minimal. It will take much more than your 250r with a 310 kit run down even a stock cr500. And as far as reliability?!! The cr500 motor is one of the most well built motors ever! It is stone ax reliable that can take lots of abuse.
Ok,first,there is no counterbalancer in a cr 500,so there IS vibration,and it DOES cause some problems!Second do you know how much HP a stock 500 makes?Do you know how much a well built 310 motor can produce?If you did,you wouldnt be talking out your *Edited**Edited**Edited**Edited**Edited*!I never said it cant be done,hell Ive had 2 of them!I was only warning about some problems,is that so bad?

hoser
08-07-2006, 05:40 PM
blah what really sucks is i did some work on my motor today, got the jug off finally. Looks like i overheated it bad enough to seize it for a few seconds. The cylinder looks like it may be ok with hone but the piston is trashed.

I shoulda just put it up for the week. oh well. Learn the hard way don't I?

I'm at the 2mm over weisco now. does anyone know if anyone else makes a piston bigger? i think I could get by with a new 2mm but I'd rather go to the next size. blah.


What kind of hone did you use to hone the cylinder?


A ball or flex hone will just follow the irregular surface of the bore, a good ridged hone will show you some of the cylinders imperfections, a skim cut in a boring machine will show you for sure.

The attached pic is of a Blaster cylinder on the stock bore "that just needs a hone" the 3 blue arrows show you the area where the cutter it hitting the bore.

More pics and write up here http://12.215.122.222/phpBB2/viewtopic.php?t=2366

Louis Mielke
08-07-2006, 06:28 PM
Ok,first,there is no counterbalancer in a cr 500,so there IS vibration,and it DOES cause some problems!Second do you know how much HP a stock 500 makes?Do you know how much a well built 310 motor can produce?If you did,you wouldnt be talking out your *Edited**Edited**Edited**Edited**Edited*!I never said it cant be done,hell Ive had 2 of them!I was only warning about some problems,is that so bad?



Whoa, didn't say there was no vibration now did I? Said it wasn't that bad thanks. Second, never said that a 310 couldn't beat a 500. Speed is just a question of money, whoever has the deepest pockets can be a winner.

And if I remeber correctly I haven't been talkin out my (I'm not gonna invoke the word filters). You seem to be the one getting all huffy all of a sudden.

And honestly so far the only one who's given any valid "problems" with the CR500 trikes is Billy, and I believe he has several trikefest drag trophys so I tihnk he has some room to talk. Oh and I wouldn't say anything like, OH well I'd have beaten him, The 500s killed so many different bigbores that weekend its not funny.

Chill out man, its not worth getting huffy about it.

Louis Mielke
08-07-2006, 06:30 PM
What kind of hone did you use to hone the cylinder?


A ball or flex hone will just follow the irregular surface of the bore, a good ridged hone will show you some of the cylinders imperfections, a skim cut in a boring machine will show you for sure.

The attached pic is of a Blaster cylinder on the stock bore "that just needs a hone" the 3 blue arrows show you the area where the cutter it hitting the bore.

More pics and write up here http://12.215.122.222/phpBB2/viewtopic.php?t=2366


Yeah I know thats why I'm so appreahensive about what to do with it. A local machine shop did it and I knew it was gonna be iffy. I think I'm just gonna get it resleaved back to the stock bore, maybe LA sleave unless you can suggest a good shop. I've got some time before next TF so I'm in no hurry.

atcsteve
08-07-2006, 07:54 PM
No huffyness here bro,just didnt like someone telling me a stock 500 will out run MY r's,I know better,from owning and racing against them. Its all good!! I loved my 500's,and kinda want another.There is nothing like the back-end power of a cr 500!!!!!! How is that 500 of yours?

3Razors
08-07-2006, 08:43 PM
No huffyness here bro,just didnt like someone telling me a stock 500 will out run MY r's,I know better,from owning and racing against them. Its all good!! I loved my 500's,and kinda want another.There is nothing like the back-end power of a cr 500!!!!!! How is that 500 of yours?

Do you mysteriously know my knowledge of engines? I know very well what good example of 310r hp is. There are a very few running around that have been built by the right builder/tuner that are capable of 60hp on gas with every trick thrown at them. Most however are owned by squids and they are very lucky if they get mid to high 40's out of them. Now a box stock 500 off the showroom floor will do 60 minimum depending on the year. With just good porting,headwork, and tuning you will be at 75hp easily!! With twice the torque!

Bring your 310r and I will bring my 500 trike to olds hill this year. And I will show you what whoopin it will lay on it. It has never been beat by any 310, 330, or 370 prox jug motor. All in good fun of course.

atcsteve
08-07-2006, 09:32 PM
Oh im sure your 500 will out run mine,but we were talking about a stock one,and I'll take that race anyday!You on the other hand need to run with the big dogs!!! Just too keep it fun,I do have a powervalve motor being built,hopefully it will be done soon!!Then I may have a better chance!

Louis Mielke
08-07-2006, 10:44 PM
i'm in love with the torque of my 500. ONce its back o nthree wheels with the inverted cartridge forks the geometry should be million times better.

Other than that I just gota get my jug back together. As stated earlier in th post, due to some head gasket problems I momentarily seized on my last bore. It still ran at the end of the day, but I'd rather just sleave it and get it over instead of hoping the current bore would last with a new piston.

Anyone have any recomendations for a place to sleave my cylinder? LA wants $420 to do it including new piston/rings.

KASEY
08-07-2006, 11:51 PM
ouchhhhhhhhh on the $420!! what about ,,,,,,,,, i know ,,,,, but here goes,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, ebay,,, LOL SORRY.


I have seen several cylinders on there ,,, now if your in love with your port job like i am,,,, maybe someone can do a transfer to a younger cylinder,,,, AND i am on my last bore too,,,,,, so i am knocking on wood here,,,, at least i only have one season on mine,,,, but my 500 talks to me real well,,,, it has kept me informed about how thirsty it gets ,so i listen closely. moving from washington to phoenix was real traumatic for it too,,,, it does not like the dust!!!! :D :D :D :D

Louis Mielke
08-08-2006, 07:46 AM
Kasey I wish I had your experience. Iím terrible at jetting kit and caboodle.

I know what you're saying on the $420. I know I can get the sleeve for less than $80, piston under $100 so I'm like jeeze thatís some mark-up or they really charge high labor.

I wouldn't be even doing anything to the jug if it wasn't for my stupidity. Just had to run the drags at TF, couldnít just let it sit until I could check out the head. lol Didn't even do well at the drags cause I was worried about running it easy. As I said I learn the hard $ouch way.

I thought about just getting a new jug from Honda. $275 and the 86 is still available, unless they're just the new jugs matched to the old part numbers. Only bad thing is then my decompress is a wash, I'd hafta pay to get it done again. I know its not bad to start it without it but I'm using the Yamaha blaster kicker and don't know how long that would hold up without the decompress.

So far I've been pleased with the power delivery and as far as I was told it was a stock 86 jug. Everything I read says the newer jugs, the porting makes the hit kinda tame so I really want to find another 86. My question then if I got a new jug would be what piston do I go with. I've always ran weisco but I'm wondering if I had run a pro-x or stocker if I would have ever seized. probly dumb thinking, the weiscos are suposed to run tighter tolerances. I did make sure the exhaust bridge was relieved and thats not where it looked like it wedged at. blah. Man toys cost so much money. lol

Suggestions are appreciated!

Bryan Raffa
08-08-2006, 02:27 PM
how bad is it really louis could it get by with a ball hone and some new rings? Or did it get chewed up?

Louis Mielke
08-08-2006, 04:10 PM
the cylinder is questionable. Most of the cross hatch is still in the bore except for two spots opposite of each other near the side transfer ports. The piston has two spots on opposite sides that you cuold file your fingernails on. I would not use this piston whatsoever. The cylinder though I believe could go either way. I'd rather be safe than sorry. My only other thought is hone my jug, throw a new piston in it and ride on that while I search out another jug to get done as my backup.

Whatever happened, which I assume is it seized, it was very brief and somewhat minor. As I said it still ran at the end of the day. I was babying it all weekend trying to avoid something like this. blah. Thats what I get for ridding on a questionable head gasket.

Darius1502
08-08-2006, 05:37 PM
Louis,

How many total CCs's will the CR 500 be up to with the 2mm bigger piston?

Are there big bore kits available?

Louis Mielke
08-08-2006, 06:06 PM
using a very basic calculator i found on the net approx 514cc. Of course it could be wrong.

I don't know of any bigbore kits that are availible although brap said he owned such a beast.