r-ex conversion

[la400ex]

I know yall are tired of hearing about this but i dont know what to do. Some people say it will work and some people say its a bad idea. What should I do?

[holeshot19]

how much 4 the busted engine:eek2:

[Steve-o 400EX]

I think you should stay with the 4 stroke. Its a lot less hassle. Good luck with it Ant.

[la400ex]

holeshot, just make me an offer.

Steve-o, lol, i dont think I can have any more hassle than ive already had.

[Steve-o 400EX]

Originally posted by la400ex
holeshot, just make me an offer.

Steve-o, lol, i dont think I can have any more hassle than ive already had.

LOL, Yea thats true, I saw the couple threads, especially the last one, that definately was not pretty. Have you found any motors yet??

[la400ex]

Yea, i found a couple motors. I wont have enough money for a couple weeks though. If one of the ones that i found is still available when I get the money, i will buy it. I gotta sell more parts before I can do anything. Later

[dirty_d73]

put a xr450 motor on it....it'll fly!!!! :eek2:

[muff]

if i were you i'd cry...but then after that I would just buy another ex motor, you've had enough problems as it is and the ex motor will bolt right up with no riggin or anything, then u dont have to worry about gettin it to fit right and having to buy a 250r carb and stuff

[300EXRocket]

Saw this engine on Ebay, just thought I'd share in case you were interested.

400EX Engine (http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2405116135&category=34284)

[roostu]

Well if you don't want to mess with putting another motor in there then stick with a 400ex....but think about he possibilities. You can find a good fuel injected 600 - 1000 cc street bike engines on ebay for 700 - 1200 dollars. I have heard that new 400ex motors are like 2000 dollars. And just some numbers, a gsxr 600 motor puts out 114 hp BONE STOCK. And it has fuel injection (no jetting problems) that makes the raptor 660 motor look like a sh1t.:eek2: Just my 2 cents.

~Roost-U

[TRX_Thumper]

i think stuffin a streetbike motor in a quad makes it junk...so much heavier...loss of handling..to much motor for chassis...thats a nope

[roostu]

Originally posted by TRX_Thumper
i think stuffin a streetbike motor in a quad makes it junk...so much heavier...loss of handling..to much motor for chassis...thats a nope

your opinion.

~Roost-U

[NTPRacing#19]

yea you wanna street bike motor buy a street bike. want a quad buy a quad. quad and streetbikes dont mix. pointless and junk afterwards.

[OutlawEX]

Originally posted by NTPRacing#19
yea you wanna street bike motor buy a street bike. want a quad buy a quad. quad and streetbikes dont mix. pointless and junk afterwards.

Very true

[EricB]

how can you guys say that a street bike motor in a quad frame is junk? how can it be junk if a guy just wants a super fast drag bike??

also i don't see how a 250R motor wouldn't be worth it? if you have the time and money i'm sure it would be. think of the things you'd have to change, you'd need a radiator and mounts, motor mounts and a CDI..course everything else for the engine, but the only things you would have to fab are radiator mounts and motor mounts. not really that hard =/ but i don't have personaly experince of doing the conversion, but logicly it shouldn't be overly dificult.

[TRX_Thumper]

yeah thats the only time a streetbike motor is ok in a quad frame..is in draggin..but stil i wouldnt do it....

[speedjunkie]

Those off you that are against a street bike motor in a quad have not seen one climb comp hill at Buttercup at 88 MPH!!!!! I have gone on dune rides with the guy and it did really well. The only down side to it is that it was in a Banshee frame. We all know how that suspension is:D

[roostu]

Mabey not good for trails but there is no comparison in the dunes. And if you havent ridden one then you have no idea what they handle like.

~Roost-U

[lil'redrocket]

Service honda sells brand new CR250, 400EX, and CRF 450 engines.

[speedjunkie]

It all depends are where you ride. In the woods or screaming down a trail through the desert it would not handle as well as a stock bike, MAYBE. If the guy that builds it takes his time he can get it balanced out fairly well. As far as the dunes, take it from me, if you have to ride behind the guy with a street bike motor in his bike, ride WAY behind him:devil

[Steve-o 400EX]

Originally posted by TRX_Thumper
i think stuffin a streetbike motor in a quad makes it junk...so much heavier...loss of handling..to much motor for chassis...thats a nope

I agree, if you ask me its a really bad idea unless all you do is drag your machine, which i'm sure he doesnt. You couldnt jump or trailride good at all. I think even a 250r motor is not worth it even though its a great motor. 4 stokes have a smoother powerband and require a lot less maintenence.:rolleyes:

[roostu]

Originally posted by Steve-o 400EX
I agree, if you ask me its a really bad idea unless all you do is drag your machine, which i'm sure he doesnt. You couldnt jump or trailride good at all. I think even a 250r motor is not worth it even though its a great motor. 4 stokes have a smoother powerband and require a lot less maintenence.:rolleyes:

2-Strokes DO NOT require more maintenance. They have very few moving parts compared to a 4-Stroke. And don't tell me you have to rebuild them often either, I have ridden on a stock bore for 2 years before I sold the bike and the new owner still has the same engine and it still has good compression. The bike was an 86 so that’s 16 years on the standard bore. And in the case that the engine does need to be re-done the cost of the piston/rings/boring/honing only cost 225.00, and takes less time to completely finish then installing a hi compression piston in a 400ex.

Now on the subject of whether or not la400ex should put in a street bike motor prolly not. But that’s his decision.

And there really is no comparison to a street bike quad in the dunes, and you can not comment on this unless you have actually ridden one.

~Roost-U

[Steve-o 400EX]

There is only 1 reason that I would put a street bike motor in a 400ex and that is for dragracing. Otherwise keep the motor in it that should be in it.

[roostu]

Originally posted by Steve-o 400EX
There is only 1 reason that I would put a street bike motor in a 400ex and that is for dragracing. Otherwise keep the motor in it that should be in it.

So you disagree with putting anything but a 400ex motor in it?

~Roost-U

[Steve-o 400EX]

Originally posted by roostu
So you disagree with putting anything but a 400ex motor in it?

~Roost-U

Not totally, an R motor would be cool, but i would personally stick with the 400 motor. Nothing against the R motor or anything, I love 250R's but I prefer 4 strokes. I also think it will cost him more money to do the conversion, if he keeps the ex then there is no changes just bolt it back in. I am not saying that these other motors would not be cool but i am trying to give him advice on what will be most cost effective and easy. This is what he wants to know, not a fantasy motor.

[roostu]

For ease of installation only would I agree with you on sticking with a 400ex motor.

la400ex this is a cross roads of sorts for you. You already have to put another motor in regardless of witch one.

Option 1: So here is the dilemma.....put a 400ex back in and gain no power over your old bike, but have a very easy install.

Option 2: Have a harder install, but gain power. You will also go with a more modern engine design (not in the case of a trx 250r) but in the case with the other choices you get liquid cooling. This seems to me the best option because you can spend about the same amount of money on a better motor and get more power OUT OF THE BOX, plus with the same amount of money you would use to mod your 400ex motor you could mod the new one and be lengths ahead of other 400ex riders.

The decision is ultimately yours to make I am just laying out the options.

~Roost-U

[roostu]

Oh I forgot option 3 :devil

Option3: God forbid you should ruin the bike and put a street bike motor in and have a really fast hill shooter AND a great dune machine. (This option is prolly not for you) It is not an option that seems accepted (by people who have never ridden one) but an option never the less.

~Roost-U

[Steve-o 400EX]

The point your missing is he is not looking for a BRAND NEW motor!!! He already said he has a small budget to work with. He is looking on ebay for a deicent used motor. Not a brand new crate motor.

[roostu]

You still have to buy the motor regardless of witch one NEW or USED and the fact is that all the motors discussed in this thread have been around the same price, besides the street bike motors (don't agree look on ebay and see for yourself).

So that does not change the options listed above.

~Roost-U

[AndrewRRR]

Maybe first we should find out what kind of riding he does.
Putting a street bike motor in isn't a small affair either. Mine required cutting out the lower frame rails and fabricating new ones (among many, many other things). Also if you don't get a longer swingarm... well, you'll wish you had.
I wouldn't do a 250r motor for a few reasons. One of the biggest being that you will have to try to find a 14-17 year old motor that is in really good condition, as opposed to finding a 0-5 year old engine that is in good condition. Plus all the issues you'll find when installing a 2 stroke liquid cooled engine in a frame meant for a 4 stroke air cooled motor (all the little stuff can nickle and dime you to death).
On the other hand, if you do just ride dunes, I can't imagine wanting to put a 400ex motor back in when you have the option for more power now. I think we need to know what type of riding he does. If there is any jumping or fast trail riding involved we can eliminate street bike motors right now.

[AndrewRRR]

Originally posted by speedjunkie
It all depends are where you ride. In the woods or screaming down a trail through the desert it would not handle as well as a stock bike, MAYBE. If the guy that builds it takes his time he can get it balanced out fairly well. As far as the dunes, take it from me, if you have to ride behind the guy with a street bike motor in his bike, ride WAY behind him:devil

Absolutely!

[roostu]

I agree with andrewRRR totally. I am almost sure we can eliminate the streetbike motors right now because of the cost required to make them work.

~Roost-U

[speedjunkie]

AndrewRRR tell us about the bike in the pic.

[AndrewRRR]

Thats "Casper", back when it had white maier plastic (where it got it's name, it was white as a ghost). It's an '86 Suzuki LT250r with a Kawasaki Ninja 600cc engine that has some head work, custom exhaust, etc. It's a fun drag/dune bike. It's suprisingly humble and reliable to ride. The only problem is the turning radius is wide because of the exhaust (front tires can't turn too far without hitting the headers), and you can't jump it...well, you really shouldn't jump it, that motor weighs twice as much as a LT motor. The power comes on very smooth and it has a very wide powerband (4 cylinders), so it's not a violent ride. That pic was taken in 3rd gear (3 gears to go). Someday i'll wind it out in 6th with my GPS on to see what it will do. It's geared as short as you can go, and 6th gear is still over 120mph :rolleyes: Not too safe on a quad that narrow.
I will probably put a GSXR or R1 1000cc motor in it sometime this year... I wanna go faster. haha here's another pic with the factory plastic (the maier stuff was kinda beat up). I'll get more detailed pics if anyone wants em Oregon350r@aol.com

[Steve-o 400EX]

Originally posted by roostu
I agree with andrewRRR totally. I am almost sure we can eliminate the streetbike motors right now because of the cost required to make them work.

~Roost-U

Okay, now u agree with him and he recommended the 400ex motor as I did, but u flamed me for making that recomendation? WTF!:huh I dont know about you but i knew that it would cost major cash to put in an R or streetbike motor, but earlier you said it would all cost the same??

[roostu]

Originally posted by AndrewRRR
Maybe first we should find out what kind of riding he does.
Putting a street bike motor in isn't a small affair either. Mine required cutting out the lower frame rails and fabricating new ones (among many, many other things). Also if you don't get a longer swingarm... well, you'll wish you had.
I wouldn't do a 250r motor for a few reasons. One of the biggest being that you will have to try to find a 14-17 year old motor that is in really good condition, as opposed to finding a 0-5 year old engine that is in good condition. Plus all the issues you'll find when installing a 2 stroke liquid cooled engine in a frame meant for a 4 stroke air cooled motor (all the little stuff can nickle and dime you to death).
On the other hand, if you do just ride dunes, I can't imagine wanting to put a 400ex motor back in when you have the option for more power now. I think we need to know what type of riding he does. If there is any jumping or fast trail riding involved we can eliminate street bike motors right now.

Read the post CAREFULLY Steve-o. I agree with the part about trying to get a motor that is only 0-5 years old (xr450,cfr,etc,etc). Does that say 400ex??? NOPE. Also just because he doesnt put a streetbike motor in does not mean that he can't put in a motor with more power. We need to know what he is going to do with the bike.

~Roost-U

[speedjunkie]

Bottom line, It is his decsion. We are just here to offer advice.

Steve-O , I am getting tired of people like you that dont fully read and UNDERSTAND a post before you make a smart ***** comment about it. Hooked on fonix workd for me! My advice to you is to think about what you type before you chime in with some dumb ***** comment. Now before we get banned, PM me if you have more to say. Lets keep this thread as clean and helpfull as possible

[speedjunkie]

Andrew,
That bike is cool man! It looks like you spend most your tim in the sand. Have you ever thought about re-doing the exhaust to get a better turn radius?

[la400ex]

I mostly ride trails, sand (by a river, not dunes) and MX. The main purpose of the bike will be MX when its done. I would love to put a crf or yz but i just cant afford it. Im on a limited budget. I might trade my ex frame for an R frame if its in good shape and start from there. Later, Ant.

[speedjunkie]

la400ex,
Now that we know what you plan on doing we can offer some true help. I ride both 4- stroke and 2-stroke(mostly 4-stroke), I love the 4-stroke because it has a broader power band and you can lug it through the trails if you want to. The 2-stroke is faster usualy and has a more aggresive power band. I think i would stick with a 400ex if I were in your shoes. I just feel it is better for all around use. Lets hear from some others and see what they think:ermm:

[roostu]

Andrew that bike is really sweet. I will be emailing you about those detailed pics.

~Roost-U

[TRX250XFIRE]

Aftger reading this long freaking post i still say that u should stick with the 400 engine. Its going to be better for ur all around use, and there will not be any hassle when putting it in.

[AndrewRRR]

If I throw a different motor in I'll probably redo the exhaust to get more tire clearance. If i run the skinnier front tires I can turn sharper, but the wide ones look cooler, and I don't ride trails with Casper anyway, that's what my R is for :)
I would say stick with a 400ex motor if you ride MX and trails. A R motor can be made faster for less money, but if you need low end power, it's hard to beat a 4 stroke. Besides, good, complete 250R motors are few and far between, and the owners want a ton of money when they sell them. Just rebuilding a complete tranny on one can cost you $2K, so you want something that is gonna be in good condition.
I say fix your EX.

[Steve-o 400EX]

You know, you should really find out what I know before you make yourself look like a SMART *****. I already knew what kind of riding he does through PM's and I knew he was on a small budget, which automatically boots the other two ideas. So now that you both made yourselfs look like idiots, lets get back to helping Ant and not continuing this stupid arguement. Also, speedjunkie, how can you say you are getting tired of seeing something when you only have 42 posts. I have been here a bit longer than you.

[speedjunkie]

Steve-o, just because I have few post in comparison to you dosen't mean I haven't been reading post made by other people. If you had shared you vast knowledge of la400ex with the rest of us, this thread would have never gotten to this point. But instead you decided to flame Roost-U when you could have easily explained yourself and your oppinion. Lets drop this flame war and start acting like the mature adults we all wish we were:devil No hard feelings on this end.


La400ex, now that we know all the deciding factors I would fix or replace the 400ex motor. It offers great low end power for those trail rides and it can be made very fast. Yes it will cost more to make it as fast as a 2-stroke, but you can do that later down the road. I think the important thing is getting it back together so you can have something to ride. I know it would drive me crazy not having anything to ride:(

[la400ex]

Looks like the 400ex motor will be the best thing to do. I really wanted to try putting the R motor in. I still might, who knows. I think im gonna buy me an R frame and build one over time. If i could ever get any of these parts sold, i could get started on whatever im gonna do. Oh well, just gotta wait. Thanks, Ant.

[Steve-o 400EX]

Originally posted by speedjunkie
Steve-o, just because I have few post in comparison to you dosen't mean I haven't been reading post made by other people. If you had shared you vast knowledge of la400ex with the rest of us, this thread would have never gotten to this point. But instead you decided to flame Roost-U when you could have easily explained yourself and your oppinion. Lets drop this flame war and start acting like the mature adults we all wish we were:devil No hard feelings on this end.


La400ex, now that we know all the deciding factors I would fix or replace the 400ex motor. It offers great low end power for those trail rides and it can be made very fast. Yes it will cost more to make it as fast as a 2-stroke, but you can do that later down the road. I think the important thing is getting it back together so you can have something to ride. I know it would drive me crazy not having anything to ride:(

I really wasnt trying to flame roost u, if you read all the posts you can see this but he just kept comming back. This is now over as you said so lets get on with it.

Ant, i think it would be a cool idea like you just stated to build an R over time. I just think it will be the most cost effective to put the ex motor back in.

[AndrewRRR]

la400ex: what's wrong with your EX motor anyway? What happened to it? How much is salvagable?

[la400ex]

AndrewRRR, Go here
http://www.exriders.com/vbb/showthread.php?s=&threadid=46496

[AndrewRRR]

niiiiiiiiiiice! lol

[jaspurx]

so , what do you want for the motor you bombed ? i need a good challenge project!! i think i could squeeze a little life out of it!!or at least give my son a science project! let me know!

[cotttonwoody]

I dont know if someone said this but i think it would be cool to put a newer CR250 engine instead of a 250r.

[la400ex]

Dang, i figured that the 400ex motor would just walk away from the R motor in the poll. I guess a lot of people that posted didnt vote. Well, now i have to wait to see what hotcams is going to do anyway. Thanks, Ant.

[jaspurx]

i did not vote because there was no specified model 250r motor. its like this , if it was a `89 trx250r motor , i`d take the r with a fresh rebuild. if it was a brand new cr250r motor , i`d take the ex motor , because the r motors for `03 are so soft on the bottom that it would need to be moded ant tweaked to even have a shot , but if done properly , the powervalve would be the big difference!!!! but right out of the crate , late mid , and top end is where the r`s power is , put that in a quad and you got a 250r that runs like a banshee`s powerband , who`d want that????? thats why i did not vote!! just because ricky carmichael`s bike pulls does not mean what you see on the showroom floor can run!!!

[la400ex]

Sorry, i meant an 86-89 trx 250r motor. I wouldnt put the cr motor because it doesnt have a counterbalancer. It would vibrate too much. I rode a 2002 cr250 and it seemed like it had power everywhere to me but i didnt get to ride it long enough to get a good feel for it. Ant.