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John B
03-12-2005, 10:21 AM
I have just bought an 05 KLX250. Was gutless. Fixed carb slide, airbox, and fitted full Staintune system. Also ripped off de ice circuit. Much better, but I want more!
Am intererested to hear from anyone who has taken a 250 beyond 292 and any troubles. My research seems to indicate that water passages in 250 cylinder are concentric with those in 292 cylinder, so all upgrades to KLX300 should apply to KLX 250. Am thinking of around an 80mm bore as I believe Wiseco make a piston this size. Any one like to add there 2cents worth?

WAYNEKER
03-12-2005, 01:33 PM
john not sure if its any help to you or not but, a guy down here AMC has a klx250 and this thing hoots along. Maybe you could pm him about what mods he has done.
Like i said this thing is no slug.

Vash
03-12-2005, 01:50 PM
I read that the KLX300 cylinder slips straight onto the klx250's

Head Gasket #11004-1314
KLX300R piston #13001-1463
KLX300R cylinder #11005-1982
Piston Pin #13002-1109
Piston Clips #92033-1054
Cylinder Gasket #11060-1740
Carb Needle #16009-1912
Needle Clip #92037-1401
Needle Spacer #92143-1667
Needle Jet #16017-1368

All this for about $900AUD

John B
03-12-2005, 04:15 PM
I know about the 300 kit - my dealer wants to sell me one and I could fit it myself in an afternoon. I like the idea of retaining the nikasil bore with the 292 as well, but even more power is appealing. Every cc counts and why not have them if you can?
I wanted aDRZ400 but am not tall so found it intimidating. The KLX is just right but I want power approaching that of the DRZ - especially low range power.

myall
04-12-2005, 11:18 AM
I've read that you can bore a KLX250 up to 300, and then stroke it to 340. Do a search at Thumpertalk (KLX section) (http://www.thumpertalk.com/forum/forumdisplay.php?f=27).

Here's a couple I just found...

klx 250 into a 300? (http://www.thumpertalk.com/forum/showthread.php?t=219836)

365 or 340 bore kit? (http://www.thumpertalk.com/forum/showthread.php?t=126480&page=2)

John B
04-12-2005, 03:02 PM
Thanks Myall,
It seems you are famous (just a little) - I have been talking with Seahorse (now TE250) lately and he recommended you as having some experience on this bike. I have had this KLX for only a few weeks, and having done the above mods, am still wavering over the next. I am now more and more convinced that any 300 mods written about in Thumper Talk apply equally to the later 250s. I do not want to fit a stroker crank yet. At a 6mm stroke increase it will only give 10% displacement increase. I am away from home (at sea) at present and have time to think - TM33 or big bore?? Clearly you have gone the TM33 route and I have only heard good about this carb - except the fitting process - did your carb come with the spacers??

AMC
04-12-2005, 11:11 PM
John B
heard some dealers were supposeto be giving the 300 kits away with all 250 sales as a kawasaki promo thing.
AMC

sdr
05-12-2005, 02:44 AM
340 is about the limit for the KLX, on most accounts of what I've heard. The 365 kit doesn't seem to last that long on the 300s.

Here's some info on the 340 kit: http://www.xrstuff.co.uk/bigbore.htm#KLX300%20KIT

From memory, the only person I know with the 365 kit was a guy in the US on the planetklx forum, although if you email Jerry from 4Stroke works in the US, he can give you all the info. They took over from Stroker when they went out of business.

http://www.fourstrokeworks.com

Good luck, and post up some pics if you do it.

cmg
05-12-2005, 09:35 AM
some guy up here in QLD (Francis I think is his name) has a fuel injected KLX300, apparently did it all himself, he tagged along with us on a ride once, unfortunately that's all I know

sdr
05-12-2005, 09:45 AM
Yeah,

Francisco built the whole thing himself - fuel injection, mapping, computer.

myall
05-12-2005, 10:50 AM
Yeah, Seahorse and I talked quite a bit, back when we was on the same team. ;)

I'm sure a 300 with a new carby would be great - but if that's not enough power, I'd say go for a different bike. I enjoy my bike, and the TM33 was by far the best mod I've done, but it won't compete with the big bikes (when it comes to power, speed & front lifting ability). Mind you, when the track get's rough, the bike gets me through with little trouble (while the other boys fight for their life).

Anyway...
The TM33 is perfect for the 250, but yes, requires frame grinding and a spacer (even when bought as a kit). If you don't get a kit, there's a bit more messing around to do (incl. carby grinding). A local shop made my aluminium spacer, at a steal of a price. Worked great.

For a 300 / 340, there are more carby choices: TM33, TM36 and Keihin FCR 35mm. I don't have experience with those, so I can't comment. From what I've read I would agree with sdr, that 340 is the limit (when coming from a 250).


Thanks Myall,
It seems you are famous (just a little) - I have been talking with Seahorse (now TE250) lately and he recommended you as having some experience on this bike. I have had this KLX for only a few weeks, and having done the above mods, am still wavering over the next. I am now more and more convinced that any 300 mods written about in Thumper Talk apply equally to the later 250s. I do not want to fit a stroker crank yet. At a 6mm stroke increase it will only give 10% displacement increase. I am away from home (at sea) at present and have time to think - TM33 or big bore?? Clearly you have gone the TM33 route and I have only heard good about this carb - except the fitting process - did your carb come with the spacers??

Barrel
05-12-2005, 05:58 PM
I also heard there was a kwaka deal on new KLX's offering a free 300 kit.

Deffinatley the TM33 mod is the way to go. Quite a financial outlay but well worth it. If cash is a concern the next best thing is a Dynojet kit for the CVK. I have seen graphs with some decent gains using the Dynojet.

The next best thing you could do for it would be have the suspension sorted.

You can find more info about the conversion in this thread.

http://www.dirtbikeworld.net.au/forums/showthread.php?t=11825&highlight=TM-33

big fella
05-12-2005, 06:56 PM
I thought their was some offer of the 300 kit with the sale of KLX250's..Your dealer should be able to sell you on for just under $600.00.

I built and rode the 300 kitted bike that was in Dirt Action a few months ago and recon it was not a bad thing in the bush

Shock treatment did the fork and shock as the forks inpaticular where very mushy, the 300 cylinder and a staintune pipe realy livened up the motor and a larger rear sprocket helped it in the tight stuff, with these mods it's no WR killer but is a little ahead of the DR and TTR250's....still cheep and relieable .

The bigger kits are all strokers and need cubic $$$$ to complete

MrGenius
08-12-2005, 05:33 PM
Keeping tabs on this :)

John B
08-12-2005, 09:22 PM
Thanks for all the above.
Am more convinced now that the genuine 300 kit is the way to go. IF they can be had for $600 - this is good value. I suspect that this may be the price if you buy a new bike now. I have put the squeeze on my local dealer and hope he can do one at this price for me. He has yet to phone me back.

MrGenius
08-12-2005, 09:26 PM
Ring Serco in QLD (http://www.serco.com.au) , i spoke to them today, they have the 300 kits there in stock and they are pretty cheap even retail price. Thats a Wiseco piston kit and the sleeve to suit.

John B
09-12-2005, 11:18 AM
Ring Serco in QLD (http://www.serco.com.au) , i spoke to them today, they have the 300 kits there in stock and they are pretty cheap even retail price. Thats a Wiseco piston kit and the sleeve to suit.
The trouble with this option is that you have no spare barrel. If indeed I can get a kit for $600 - this will be good value.
I just want to remark on the full Staintune pipe my bike has. It has no clamp to join the pipes. At first I could not push the pipe into the silencer and thought I would have to take it back. A little smear of "never seize" solved the problem, and should ensure it should come apart OK. The guy at the factory said they are made like this (close fitting, without a clamp) to allow for flex, and indeed you can see how the pipe has moved about 2-3mm in and out after a ride.
The new Staintunes have a different baffle than previous pipes and make a lovely mellow sound.

MrGenius
09-12-2005, 12:57 PM
Ahh ok :)

After reading all of the links posted around the place id really like to do the 340cc setup for this bike, it seems to be the best for making a decent amount of extra power although a little on the expensive side.

John B
09-12-2005, 05:49 PM
Ahh ok :)

After reading all of the links posted around the place id really like to do the 340cc setup for this bike, it seems to be the best for making a decent amount of extra power although a little on the expensive side.
Yes, a 340 thumper kit would be lovely which is why I want a spare barrel - can always go back if the 340 blows up. When I bought this KLX I was so disappointed with the power that I said to my son (who also rides it) I am going to double the power of this bike! Since the bike has somewhere between 14hp and 18hp - depending upon which source you believe, this means I have to aim for 36hp before the job is done.

Seahorse
10-12-2005, 02:37 PM
Pretty sure the genuine Kawasaki barrel is "Nikasil" coated to boot. I think the American barrels are plain

If you like John, I can check with the local Kawasaki shop (Newcastle) for a price on a big bore kit....it may keep your local dealer "honest".

John, I havn't forgotten the article I promised to photocopy for you..hopefully Iwill be able to do it next week.

Myall.... Havn't regretted trading the KLX for a Husky...The only money I have had to spend on it is for a set of barkbusters. Parts are similar in price if not cheaper than kawasaki..What I do miss is the comfortable KLX seat...the Huskies is diabolical.

myall
10-12-2005, 05:06 PM
Myall.... Havn't regretted trading the KLX for a Husky...The only money I have had to spend on it is for a set of barkbusters. Parts are similar in price if not cheaper than kawasaki..What I do miss is the comfortable KLX seat...the Huskies is diabolical.
Heh, you might have to do a seat mod then :)

So how far did you go with the KLX before you gave it up? Did you do the dynojet? I'm curious to know the performence diference you've found. I'll take a guess and say your TE250 has a better throttle response (due to the keihin carby). Do you notice the weight difference much?

Seahorse
10-12-2005, 08:38 PM
G'day Glenn......

Sold the White Brothers Pipe and Manuals to Dirty Blond....

Sold the DynoJet Kit to a Guy on Kangaroo Island...Havn't heard if he installed it yet.

Dunno what I'm going to do with the Husky seat....the only advice I have been given so far is to Toughen/Harden up....Anyway I will figure something out.

Looked at a KLX400 before settling on the Husky. To be honest with you the build quality of the KLX400 I looked at was disgraceful...still had weld spatter on the frame... too bloody lazy to clean it off before spraying.

I think the local Kawasaki agent is having problems moving KLX250's. It is a bloody good bike but should be a 300 to start with.

Still looking forward to catching up with you for a ride one day.....

Steve

John B
10-12-2005, 09:14 PM
[QUOTE=Seahorse]Pretty sure the genuine Kawasaki barrel is "Nikasil" coated to boot. I think the American barrels are plain

If you like John, I can check with the local Kawasaki shop (Newcastle) for a price on a big bore kit....it may keep your local dealer "honest".

Thanks Seahorse,
I am still waiting for my local dealer to phone me back. The Newcastle dealer's web site appears to indicate $600 for the 300 kit, but whether this is only if you buy a new 250, I don't know. I reckon Kawaski Aust. should readily sell these kits to any 250 owner for that price.

John B
12-12-2005, 07:38 PM
My dealer has come up with a price for the 300 kit - $550 - so my son is on his way there now with a cheque.
It makes me think, 1 x KLX250 on road for $7200 + free mods + $550 kit + $90 pro tapers + $250 Staintune head pipe = $8090 for a registered electric start KLX300 that will get up and go is great value. This assumes you do the installation yourself, but then to me this is half the fun of ownership. My anticipation for riding this bike is mounting.

AMC
12-12-2005, 08:13 PM
John b
who's ya dealer. Might get one myself.
Cheers

Seahorse
13-12-2005, 09:38 AM
Crikey John!!!!!!!...That would have to be a BARGAIN...My dealer was talking $1200 when I made enquiries a couple of months back..

If they had have offered it to me for $550 I would still be riding my KLX today.

John B
13-12-2005, 02:30 PM
John b
who's ya dealer. Might get one myself.
Cheers
I bought the bike form Southern Highland Motorcycle Centre in Mittagong. It is a new dealership and the only major barnd he has at present is Kawasaki. I not that the Newcastle Kawasaki dealer has a price of $600 on its web site - I feel that any Kawasaki dealer should be able to offer it at around this price.

myall
14-12-2005, 02:05 AM
I have a suspicious feeling that you'd be (almost) wasting time going for a 300, if you don't also put some time/money into the carby. The carby is the biggest problem with the KLX250, in my opinion.

I suppose it'd be really interesting to run a comparison one day..

My KLX250 with TM33 pumper
versus
A KLX250 big bore 300, with stock carby
versus
A KLX250 with dynojet!

John B
14-12-2005, 10:08 AM
Myall,
What a great idea - I may even ride up your way once the conversion is done.
I though deep about this TM33 and was almost on the verge of ordering through Hatricks. Then I really started to investigate the dynojet option. It appears it will give you almost all the power the TM33 gives, but not quite as rapid response. The 300 kit includes an adjustable needle, and clips and spacers, which you would have to order to fit a dynojet kit. So I will fit the 300 kit, then order a dynojet kit. I also believe my style of riding (I like to lug the bike now and then) possibly favours the CV type carb.
I am at work now so will not be fitting the kit until late January. I will make a post when done.

myall
15-12-2005, 07:15 PM
John,

Yeah perhaps we should compare.. and get Seahorse on it too, so he can see what he's missing. ;)

Btw my bike loves lugging around.. the TM33 pumps a nice amount of power in those low revs. Did I ever tell you that after I changed the carby, I almost flipped the bike? Had a big smile for days I did. :rolleyes:

Seahorse
21-12-2005, 02:49 PM
G'day John

I have the article photocopied and waiting to mail to you, but have misplaced your address....

Could you please send it to me in a PM

Regards

Steve

John B
22-12-2005, 10:44 AM
PM sent Seahorse,
May be losing the thread now, but as a new dirt rider I have to buy some gear, Should I buy green to match the bike or is this sort of thing considered a bit gauche??
Do KTM guys wear orange??? Easy for Big Red and Yamaha riders as these are common colours.

Seahorse
23-12-2005, 10:16 PM
Article in mail today John.....will be waiting for you when you go on leave.

As far a gear goes, I wouldn't go overboard till you decide what your are comfortable with. Wait till you have had a couple of rides with the local guys...No point turning up in "flourescent" nylons looking like a sponsored team rider if the rest of the guys are wearing jeans and footy jumpers.

However, do spend your cash on good protection gear. When you turn the KLX into a 300 you will probably start "pushing" a little harder than your ability allows, so expect a few "get-offs". At least don't ride without a good set of elbow guards as a minimum (I can recommend 661's... which are only around $40).

Luckily being a seafarer you will have a current first aid certificate....There have been a few times when I have had to practice first aid on myself after a particularly heavy fall...(dont forget to take some "Neurofen" with you when you ride).

Eventually you will want some quality body armour or a pressure suit....keep an eye in the mags or watch for specials at the local bike shop or Ebay. I just picked up a brand new Dainese Safety jacket for half price..!!!

You will also need a Camel Bak if you intend spending more than an hour out on the trail. I got myself a Fox "Oasis"....Carries plenty of water plus room for tools/mobile/wallet/tissues/first aid kit etc...very comfortable to wear for long periods as well.

Keep an eye on Ebay for cheap boots and riding gear...you can save heaps over the "inflated" bike shop prices

TeamKLX250
29-01-2006, 10:34 PM
Hi guys,
I just bought my KLX250 last Saturday (21/1/06) and I got the 300cc big bore kit and a Kawasaki bike cover with the bike for free and I payed $7100 on road. I like the power of the bike for a 250 I think it goes great. Well for now anyway maybe later I will want more :)

^roost

John B
30-01-2006, 11:00 AM
Hi TeamKLX250
I wonder if your dealer deristricted the thing before delivery? The manufactures seem to do this prior to magazine tests. How does the thing climb long steet hills? - that is the giveaway - if you have to keep changing down then you have another 7 -8 hp waiting to be untapped very easily. Other than that I think this bike handles great in the dirt.

TeamKLX250
31-01-2006, 06:36 PM
Hi John, your right about the long hills. I have some info from another forum I'm in all about hotting up KLX250 if your interested its here (http://www.advrider.com/forums/showthread.php?t=107591&page=19)
^roost

p.s dont order the carbie kit till after you read this

p.p.s.

the p/n of the 300 kit is 999A275 and retail is $600 or just under

John B
31-01-2006, 11:12 PM
Hi Team KLX250

You may have read my other postings from the site – I have already fitted the Dynojet kit and the bike hauls.
I note the comments from the other forum. You should be aware that Big K have just re-introduced the KLX250 to the USA. Previously they only sold the kick start KLX300 and prior to that the old kick start KLX250. There are some major differences in the crankcase on this earlier 250 model.
The other matter is what constitutes a “standard” 250 carburetor – it varies as to the year. Late Australian models have this ridiculous slide modification to supposedly get past ADR’s. There are two holes near the top of the slide that relieve vacuum, never letting the slide open fully. The effect is worst on hills as the engine slows and the vacuum over the venturi falls, this further closes the slide, just when you want it to open more. I called Kawasaki technical and they advised me that the bike would never go at all well until these two holes are filled.
I do not know if the USA models have this modification – I do not believe they do from the comment on other forums, hence their bikes go OK from the start, and will respond to the other modifications like airbox, exhaust, jets etc.

I have now made the following mods to my 2005 bike and the performance is excellent.
1. Carb slide holes filled (p.m. me if you are unsure about which holes)
2. Airbox lid hole size doubled ( too much noise if no lid)
3. Remove de-ice circuit and replaced radiator hose (cost $4)
4. Staintune header pipe and silencer (yes it is noisy)
5. Dynojet kit fitted – 128 jet + needle + drilled out one vacuum hole at bottom of the slide. The Dynojet needle is the secret ingredient here.
6. Options of 14/42 or 14/50 gearing
7. Pro Taper SE bars – originals bend very easily.

I have a 300 kit ready to go – it cost me $550 but came without the 300 carb needles and jet (a 128 I believe) The 250 comes standard with a larger 132 jet but a large and obstructive needle.

Happy to talk more on this subject if you wish

John B.

myall
01-02-2006, 01:04 AM
Thanks for that link, TeamKLX250.
That damned big bore kit is getting attractive....... :rolleyes: ^BGHD

I wonder how much it'd cost to get it all done for me.. I'm a bit scared of engine work..

Mad Mike
01-02-2006, 02:31 AM
The KLX250 is a top bike but it is not in the league of the high performance 250's like the wr's and crf's of today. The klx can be taken out to a 320 without stroking it (340 or so if you do). It was the same deal with the klr250's as well. Be carefull though as they did not respond too well to any extreme makeovers in the "years of trouble free riding" area. They are not a motocross bike.
Seriously though, if you are after more power at the same weight look at traiding it for a WR, CRFX, EXC or the like. If you are after less maintenence than these bikes then look at (dare i say it) an XR400-just get the front suspension worked, or KLX400 (same as the Suzuki option).
Hope that helps on top of what everyone else has said.

Mike.

TeamKLX250
02-02-2006, 04:35 PM
not a dumb question at all I'm happy with the power of mine ... at the moment anyway, maybe i'll install the kit later when i'm more used to the bike

John B
02-02-2006, 10:34 PM
[QUOTE=Mad Mike]The KLX250 is a top bike but it is not in the league of the high performance 250's like the wr's and crf's of today. The klx can be taken out to a 320 without stroking it (340 or so if you do).

Hey Mike,

Why would I want to spend ten grand on a fragile thing like a WR or CRF???
Their seat heights are all too lofty for me anyhow.
These KLXs can be made just as powerful as the newer bikes, are more reliable and at less cost.
My research indicates that the newer 250 models can be taken out all the way to 331 or 340 without stroking, should you desire this. The newer 250 cases have the same cylinder opening as the 300.
Yes, I wouldn’t mind a 450KTM in a couple of years time, but I may hang on to this great little bike at the same time.

TeamKLX250
02-02-2006, 11:22 PM
[QUOTE=Mad Mike]The KLX250 is a top bike but it is not in the league of the high performance 250's like the wr's and crf's of today. The klx can be taken out to a 320 without stroking it (340 or so if you do).

Hey Mike,

Why would I want to spend ten grand on a fragile thing like a WR or CRF???
Their seat heights are all too lofty for me anyhow.
These KLXs can be made just as powerful as the newer bikes, are more reliable and at less cost.
M
Wayyyy too tall for me I have enuff probs with the KLX, had the dealer take foam outta the seat for me, I checked the price of the crf just outta curiosity $4800 more than the KLX, no thank you. I'm told the yammie is about the same I'll stick with Team Green

Luke_N
05-02-2006, 01:28 PM
Anybody been on the dyno with the 300 kit yet?
My 99 model 250 made 25hp at the wheel (shootout mode) with a little bit of slip at high revs, made over 20 from 5krpm till the limiter... sigh, still miss that bike.

Airbox opened up, Staintune pipe and free mods.
300 kit with decent carb should be getting pretty close to that 36hp goal.

John B
05-02-2006, 10:03 PM
[QUOTE=Luke_N]Anybody been on the dyno with the 300 kit yet?

An interesting thought - but top speed suffices for me. You can get a fairly good idea what a bike will do for any given power with a rider upright, by looking up old road tests. These usually quote crankshaft power and top speed. eg and old BS Bantam with 13hp made 65mph or 105kph, a 441 Victor with 29hp made 90mph or 145kph. It takes about 40hp to do 100mph with rider upright.