Gorr 240 Kit - Opinions? Good, Bad?

[KTM Mike]

I am considering buying a used KDX for my son, and came across one with a Eric Gorr 240 kit on it (LA Sleeve liner I believe).

From some other boards, I get some rather mixed opinions on these kits. Off hand, I dont think I would choose to put one on a bike I already had (for example the KDX my other boy rides), but is there really any big issues with this conversion? I tried a search here, but get like a gazillion hits, and when I look at the posts, no mention of 240 kits in those threads! Dunno what that is happening!

Seller says he spent a great deal of time dialing in jetting, and has it right on. Has like 15 or 20 hours of use since the kit was installed.

How is the power delivery with these kitted bikes? I understand they are real strong down low, but get a mixed bunch of opinions about mid and top end. For our need, I dont see top end as much of an issue, though I dont want a bike that will hit the wall before it gets to 35 mph either! Is the power delivery smooth, with a managable hit, or is it a hard to manage hit? (this bike would be for my 15 year old son, new to bikes so I want an easy friendly to ride motor for him)

Any comments/opinions would be appreciated!

[Indawoods]

I hear they run great!
I will proly get one when this cyl runs out of tolerance but 'til then... it suits me fine. I just like plated cylinders and not rebuilding all the time....

I hear they can be pretty tough on the lowerend if you run them hard all the time, but hey.... I bet it sure feels good!

I know there is one guy who runs one here on the board, so maybe he will jump in here....

[m0rie]

On the older KDX's you lost the use of the power valves with the 240 kit. I don't believe that is the case with the H series KDX's though. Something to check out though.

[Ryan]

being 16 myself i dont really think this bike would be a problem for your son unless he is very short, I am 5'9 and it is just a bit tall for me. This is only my second bike and it is very easy to get use to. i have the kdx220 and the power is great so a 240 must be really fun. How tall is your son?

[canyncarvr]

I asked Mr G. about KIPS and the 240 once. It's (the KIPS) retained on the 'H' model, anyway.

When my plating was damaged, I considered getting it done...as long as I had to replate and all. The killer for me on the deal was the rather large 'hit' I'd have to take in the range of the bike. I commonly gotta have 70miles-per-tank. Too many 240 riders said they got way less than that.

Yes. I think aftermarket tanks are ugly and I don't want one.

Also, more than one 240 rider could not get rid of their detonation problems that showed up after their 'upgrade'. Pump gas was spec'd in every (that I read of) case..and the result was it (pump junk) could not be run.

A repeat: I thought EG plated his 240 kits..NOT sleeved 'em. Just checked his website. He does big bore kits both ways. Doesn't say if the choice is dependent on make/model/year or not.

http://ericgorr.com/services/cylrebuild.html

I wouldn't buy a sleeved bike. Just a personal preference, imo and all that disclaimer junk.

[Lutz]

I believe that all 240 kits for the KDX require a sleeve...and while there is a way to plate steel sleeves, I do not believe EG does that when he sleeves a cylinder.

I have Eric Gorr's 225 kit in mine (meaning a bored and replated cylinder, not sleeved). So what can I tell you from my experience what to expect with the 240 kit? Nothing...it's a different animal than the 225 kit in my bike.

Among 240s there are a lot of variables that will effect the power delivery...primarily year (as in powervalves intact or not) and porting layout. My understanding from talking with Mr. Gorr when I dropped off my cylinder at his shop that the 240 uses a very heavy piston, which inherently makes the motor somewhat slow to rev. It is also a fact that the heavier piston will be harder on the bottom end than a 200, 220, or 225 piston, especially if revved high/often. Whether the difference in bottom end life would be detectable, I don't know.

I agree with canyncarvr about the issues "read about" on fuel consumption and detonation on pump fuel. I also agree that I probably wouldn't buy a 240 kitted KDX, unless for a good price and after test riding. If it is otherwise a good bike, you could always buy a new top end to convert back to a 200 or 220 (or 225). I don't think that sleeved big bores are necessarily a bad thing, just that the 240 big bored KDX goes too far to work really well every time.

[canyncarvr]

Well, crappers.....

Something about that number didn't seem right...Lutz made it clear.

The 225 is a plateable 200 upgrade...the 240 is a sleeved 220 upgrade.

That is a correct statement...right?

My comment was in regard to a 225'd 200...NOT a 240'd 220.

'Consider the source!!'

One of the issues with a too-big bore on a 2-stroke: The bigger the bore, the lower the transfer ports get. They cannot be made 'higher' without the use of something like epoxy. That's problematic......

My apologies.....

[Lutz]

The 225 is a plateable 200 upgrade...the 240 is a sleeved 220 upgrade.

That is a correct statement...right?

Yeah, thats pretty much right, at least from an added displacement standpoint. You can do either upgrade to either motor...that is you can bore both the 200 and the 220 out (no need for a sleeve) and replate them to the 70mm bore in the 225...but your not gaining nearly as much displacement from the 220 (25cc's from the 200 vs only 6 from the 220). Likewise, you can also sleeve both the 200 and the 220 to get to the 72mm (I think) bore in the 240. If you have a 220 and absolutely have to get a big bore, my opinion is the 240 kit is the only reasonable option - I'll explain why...

There are some differences in the outcome depending on whether the starting point was a 200 or a 220 (at least in the case of the 225 a.k.a. non-sleeved kit). When I was at his shop, Eric showed me the differences between the 200 and 220 cylinders, and explained why the 200 actually makes a better starting point for a big bore. The ports are cast differently between the 200 and the 220, especially on the intake side. Long story short, the bored out 220 has much less metal left around the ports than the bored out 200 (and if I remember correctly it also has further from ideal port geometry). The result is a more fragile cylinder with less ideal porting (I think the less ideal porting is the bigger issue). My impression is that if you want to upgrade the 220 (short of the 240 kit) you are likely better off porting only - without getting a big bore. Gosh I hope I'm remembering all that correctly. (Anyone else remember or know otherwise?)

I'm not entirely sure how all this info applies in the case of a sleeved motor such as the 240. And I'm pretty sure none of it really matters to the original questions of this thread-but there it is anyway.

One of the issues with a too-big bore on a 2-stroke: The bigger the bore, the lower the transfer ports get. They cannot be made 'higher' without the use of something like epoxy. That's problematic......

Very true. I think that's one of the big reasons why people with the 240 kit so often report good bottom and mid with a brick wall for a top end. ...And another reason the 225 kit is better than the 240.

[KTM Mike]

Thanks for all the replies everyone! Sorry I did not jump back in with a post until now, but looks like that 240 is off the table for us anyhow. (it sold already). Separate from that, i was starting to lean away from it anyhow due to all the issues noted here.

FWIW - it was a 220 upped to 240, and from what I could tell on EG site, all of his 240s use LA Sleeve non plated. I also "heard" elsewhere that EG tends to not strongly recommend the 240s - more pushes the 200 to 225 conversions.

Meanwhile, i have tracked down another candidate for my kid - a 95 200. It is a bit of a rat bike cosmetically, but solid mechanically - recent bottom end (including tranny bearings) and top end. About the only mechanical issue it might have is a need for shock linkage bearings. I have the cosmetics covered as my other son's 200 came with extra plastic, pipe and a bunch of other stuff. Looking like a good chance this one will join the stable.

Oh Ryan - this one is for my 15 yr old who is about 5'8 or 9 so no issue seat height wise. His little bro, last year at age 12 and 5'3" got a KDX 200 and adapted easily (that kid is now over 5'8" so height issue went away rather fast!) . The 15 yr old is a pretty good agressive woods quad rider (amazing to see him slam his Blaster through tight stuff!), and a potential bike convert. Once he adapts to the twist throttle, I think he will quickly start pushing me on my KTM!

Thanks again everyone! Stay tuned - my garage is turning greener and greener... (I better go buy a spare KTM to keep that color ratio in better balance!)

[m0rie]

Ratty plastics are a good thing for somebody learning to ride 2 wheels. Sounds like a good deal, let us know how it comes out.

[dave04kdx]

I did the L.A. Sleeve 240 big bore kit on my 86. The power valve worked great, just as before. I didn't gain a lot if any on the top end. My bothers 88 ran pretty much neck and neck with my 86 wide open. I did notice a big gain on bottom end grunt. It was awesome

A couple of negative things about the 240 kit were. Heat transfer of the cast iron sleeve isn't as good. The bike got hot a couple of times at high rpm operation. But, how many of us ride the KDX's at high rpm for any extended period of time? Second, the cast iron sleeve wore quickly. I rode the bike for 2 seasons, took the head off and the sleeve was worn to the point of needing to be bored out to the next size. The sleeve had a good sized lip on the top.

[Lutz]

But, how many of us ride the KDX's at high rpm for any extended period of time?

Well...at least one! I've said it before, but much of my riding is along old railroad grades converted to trail...long, straight, and flat...lots of topped-out-for-as-long-as-you-care-or-dare-to-be-topped-out type riding...not really much fun for very long. It was during that type of high speed riding when my buddy on his CRF450R could really put a spanking on me...until the day he went a tooth lower on his countershaft sprocket...that was the day when my bike could spank his badly...and the day the rod in his motor snapped and ate the entire engine (which is still in pieces two years later-too much money to fix it-oh yeah, and he's still making payments on it. Just another reason the currently popular four strokes stink). OK back on topic...

Probably not many of us ride our KDX's at high RPM for long.

[KDXer]

Off topic but what is your avatar Lutz (the mrs thinks its an angora cashmire rabbit, I thought it was a hamster type thing).


So who's right ???

[skipro3]

That's a rabbit. It has big ears.
(my guess anyway)

[KDXSean]

That's a rabbit. It has big ears.
(my guess anyway)

I have big ears, does that make me a rabbit

[KDXer]

That's a rabbit. It has big ears.
(my guess anyway)

I have big ears, does that make me a rabbit

Maybe, do you like carrots ??

[Lutz]

I was wondering when someone would ask about that. Any more guesses?

That funny looking critter is a Lionhead rabbit; goes by the name of Simba. He's one of our family pets...the other is a turtle, a Red Eared Slider to be exact, which I've had since I was a wee little boy. On second thought, I think my wife considers the turtle to be mine and mine alone. The rabbit is litter trained and lives in its very own bedroom. It could roam the house if it wanted to, but it has never left the carpet in its room because it hates hardwood floors, even though we leave the door open. The only time we lock it in its cage is when we are gone or in bed.

Now I know what you're probably thinking. "Rabbits are for shooting and eating." I agree, hunting rabbits is fun. But believe it or not, this rabbit is a better pet than most cats or dogs. Plus he's pretty hilarious to watch when he starts tearing ass around the room.

OK. Let the ribbing begin.

[canyncarvr]

I want some video!!

..the Simba part is funny!

[Colorado Mike]

that's funny. My wife used to have a lop-eared rabbit that we named Megatron, the Attack Rabbit. He would hop around the house, but if you made eye contact with him, he would almost always jump up and buck you right in the face. That thing was nuts, but he could make you die laughing. I think he was a couger trapped in a bunny body.

[KDXer]

Cool, thanks for the update.

Those red eared sliders are awesome. Meat eaters, right ??

I have 5 eastern longneck turtles, 2 snakes, 3 pitbulls, 2 goannas, 1 green tree frog and a partridge in a pear treeeeeee.

My 7' python would leeerve Simba....