KLX's - a shared disease

[grouty]

Does your Unifilter touch and seal ok on the airbox ?
If it does, then that would point to the 'A' bracket inside the box being shorter. If I was to fit the short ones (Unifilter) then I would be able to get my fingers into the gap between airbox and filter !

I had never given the KLF300 top end a second thought. I would imagine the stud spacing would be quite different to the KLX. If I come accross a base gasket I will have a look.

[Stan S]

I had never given the KLF300 top end a second thought. I would imagine the stud spacing would be quite different to the KLX. If I come accross a base gasket I will have a look.

Grouty,
I think the stud spacing may be the same. The main difference would be the 2, 6mm hold down bolts on the cam chain tunnel. The KLF runs an outter bearing on the camshaft siimilar to a C model KLX which would also be a bonus. I think they both share the same stroke and there is plenty of performance cams and pistons available for the KLF's. I would imagine the crankcases would need opening up to take the larger liner. I will see if I can find a top end to measure up.

Regards Stan.

[sa63]

very intersting the klf option(if possible), i have pulled the topend down on the klx i have. the head and cam are dead.. the cam has lost 3-4 mm on the inlet lobe. Rockers  alsodead, must be made from cheese..!!
Bore and piston are good /bigend feels fine. its done 9000k. still started with 1 kick but rattly.

I did buy a klt roller head and cam on ebay yesterday.but would like to see how the klf thing goes.
Will measure up the airfilter

[grouty]

Well .... I'm off to buy a KLF base gasket to have a look-see

[The Stroker]

G'Day guys,
I have a 1981 KLX 250,
I have used a KZ 250 ( road bike ) barrel and head on the original bottom end.
The KZ barrel has 249cc stamped on it as opposed to 246cc which is stamped on the original KLX.
The head has a roller cam bearing on the sprocket end.
I have shaved 1mm off the head and machined the inlet port and inlet manifold to get an uninterrupted flow from the carb into the engine.
I had the original cam shaft re-machined by a bloke in Brisbane  ( Ivan Tighe ). It now gives peak performance fairly high in the rev range.
I am still running the original carby, although i did race a KLX in the early 80's with a Delorto pumper on it.
The jets I am using are a 135 pilot and 150 main, large i know and it does run a little rich but has none of the usual KLX flat spots, and pulls hard all through the rev range.
I am running 1 1/2 inch exhaust.

I ride the bike in vinduros and ride it around the place a fair bit as it is road resisted.
The handeling is great, I had the rear shocks rebuilt by RAD in Brissy, the forks are standard with ATF oil and about 8 P.S.I. pressure.
I am still in the process of making it look pretty so no photos just yet.
Hope this is of interest. by the way , my air filter is 60mm deep.

[grouty]

That sounds interesting. I have never noticed that the KZ says 249 
Is your KLX an early model (79 or 80 A1 or A2) ? This air filter thing is getting to be a pain. The customer service from Unifilter is weak at best. This should not take so long to sort out. At the very least, an email to acknowledge mine would be good. I do that for all of my customers if I do not have an immediate answer.

[grouty]

Ok ..... been looking at the KLF option 
Seems possible with a small amount of machining.

First picture is of the two gaskets (KLF 300 and KLX250) on top of each other.


The second shows the KLF300 gasket on an old KL250 barrel. The only thing that seems not to line up are the two dowels.


And another.


The last one is of the std KLX/KL base gasket on the 250 barrel.


Seems like the only machining required would be to relocate the two base dowels to fit the KLX/KL bottom end. I guess I would have to use the KLF head to make the head gasket situation easier. It would also be interesting to measure the KLX/KL barrel to see if there is enough meat to machine out and fit a KLF liner. I suspect not as Kawasaki would probably gone that route if they could.
I use a 72mm piston in my KLX at present. If the KLF top end is a go'er, then MTC do a 76mm piston. Should bump the compression up to around 10.5:1 or more.
So ....... who's going to be the first to pop up pictures of the next stage ?

[sa63]

I looked up specs on the klf 250 and 300, and were shown as having different strokes? Hard to believe though
The 300 had the same stoke as the kl/klx and the 250 was shorter
Need someone with a wrecking yard buddy for a measure up!

[zorroz]

Cheapie anyone?



http://www.ebay.com.au/itm/Kawasaki-250KLX-/150916670483?pt=AU_Motorcycles&hash=item232355a413#ht_500wt_1288

[cloggy]

 Funny, I was checking out the KLF three weeks ago
 The head studs look to be the same spacing, the strokes the same [a friend was rebuilding a klf for a customer] The klx carb would probably still fit the airbox. The klf head  has a decompressor
 The options were to get a whole top end or just a piston and liner. Actually the heads seem to share a lot of parts but we'd need to open up the barrel mouth assuming the piston fitted, but it's not Honda so it probably would. I'd guess it would work but a head gasket might have to be made. The klf uses a one piece head gasket, quite different to the KLX set up. I'd say the reason kawasaki never did it is more to do with stretching the 200kz engine just too far for acceptable durability, might be ok as a race motor though.
 Luckily reality bit and I decided not to spend yet more money, at least until I've finished the present projects
 

[The Stroker]

Pardon my ignorance, but what is a klf ?

[cyclegod]

Pardon my ignorance, but what is a klf ?

Quad (KLF) or trike (KLT) that used the same basic engine as a start point.

[Bikeaholic]

Picking up another KLX250 on the weekend. Intentions are to build up one as a VMX bike for the Viper rounds. No doubt I'll be trying to squeeze some extra out of the stock engine so i don't end up looking like a sweep rider  . The KLF mod looks intersting if it's doable. Any further developements on this?

[GMC]

It would also be interesting to measure the KLX/KL barrel to see if there is enough meat to machine out and fit a KLF liner. I suspect not as Kawasaki would probably gone that route if they could.

I don't see why not. I big bored my KLX in the day. There was a 290 (292?) option and a 170 (?) option. I went the 290 option and for this one I had to have the cases machined to accept the bigger liner.
One draw back with mine was I reckon the oil passage ended up to close to the bore.
If I had my time again I would move that oil passage further out.

[grouty]

I have been toying with the idea of moving that oil passage to an external braided hose. I guess with machining the barrel to fit a bigger liner, a tad of extra to open out the oil way would be easy.
My only concern with the barrel would be the wall thickness between the fins. If the casting is does not have enough meat then the boring will break through. I know the liner will cover it up, but this could be the source of a serious oil leak. A friend did a similar thing and overbored a Yamaha TTR250 to 300 ish. There were places where the boring to fit the bigger liner had broken through. it was not spotted until the new liner was pressed in and the engine assembled and back in the bike. Running it for a few miles produced a great deal of oil.

New KLF liners seem to be about £50 on fleabay. Maybe one of the sellers could give us the O.D