#  >  > Living And Legal Affairs In Thailand >  >  > Motoring in Thailand and Asia >  >  Kawasaki dtracker/klx250 to 300cc

## yankee99

I was surfing the kawasaki forums and found a 300cc complete upgrade kit. It was located in CA and shipped to my son in florida for $335 total. My son who was on his way here carried it so no duty or crazy shipping.  I would have liked a 330 but at almost $500 more it was hard to justify....



I really dont like to do these projects as it seems me and murphys law are one in the same. That said i havent found too many torque wrenches in these thai shops.

Here is the patient



My operating tools



Made in the home land



So today i am going to check some tolerances as i am waiting for a bike stand to be delivered.  Here i am checking the ring end gap. The rings get inserted in the cylinder. Then you use the piston to push them down about a 1" to make them square. You then measure the space with a gauge and check it against the factory spec..



Now the rings go on the piston in a specific order and the gaps also need to be positioned in the correct direction. Normally when the piston is inserted in to the cylinder a ring compressor is used. I dont have one and doing it by hand is a pain in the ass. I made my own compressor and it seems to work on my patio table.

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## draco888

interesting thread. when its back on the road give us an impression of the difference it makes.

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## Bangyai

Nice job. Hope it runs as well as you hope.

Not only do rings go on in a specific order they often need to be the right way up too ! I once bought a small Honda for 5 pounds that the owner had tried but failed to repair and had given up on it. Once I had stripped it down a bit I found he had put the rings on in the right order but with the top ring upside down.

Soon fixed that and had a runner in no time.

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## yankee99

> Nice job. Hope it runs as well as you hope.
> 
> Not only do rings go on in a specific order they often need to be the right way up too ! I once bought a small Honda for 5 pounds that the owner had tried but failed to repair and had given up on it. Once I had stripped it down a bit I found he had put the rings on in the right order but with the top ring upside down.
> 
> Soon fixed that and had a runner in no time.


Correct ever motor is different. In my case the top 2 rings go with the markings up. The bottom ring [ a set of 3] do not have a up or down just a direction for the gaps.

The rings placement is critical and as you said the bike will not run if they are incorrect.

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## AntRobertson

Yeah, interesting project. Good luck with it!

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## yankee99

Ok my stand never arrived today but like a kid i want to play with my new toys. Had some things to do today but got home around 3:30pm and shuffled the parking area around...

Ok the first thing is to drain the coolant and then remove the plastics, seat and radiators. I try and re-insert the bolts where the came from this makes assembly easier..







Both radiators have been damaged in previous falls but they still function. A guard may be needed in the future.



Ok that was easy and no issues. Next the valve cover and cams.

Before removing the cams its a good idea to bring the piston to tdc. This is done by removing the spark plug to release compression. Then you have two caps on the bottom of the engine. One is used with a socket to rotate the engine the other is to see the tdc mark.



My cam timing has been previously modified from stock but there are marks on the cam sprockets to confirm you are at tdc. I photo them and mark them for ease of reassembly.



So you remove the cam cap bolts and the cam chain tensioner then the cap comes off and the cams can be gently removed.



One more thing before you remove the cams you need to fasten the cam chain so it doesn't fall to the bottom of the engine.



After the cams are out you disconnect the fuel system and some misc hoses. You then remove the head bolts. After a lite tap with a block of wood the head will come off. Be careful as there are some alignment spacers that will fall out.



Ok so now i am getting closer. Not sure what this white stuff is on top the piston but will investigate in the morning.



Now a couple small items to disconnect then the cylinder comes off.



So did all go well yes and no. I had a near disaster at the last step when removing the cylinder.  The cylinder has a fitting that holds a spring and washer which pushes against the cam chain guide. I didnt know this and when  i removed the cylinder the spring dropped in the crank case. Well this was going to be a bad day. I was lucky and somehow managed to fish it out with some wire. Then i checked the manual and saw there is also a washer. Luckily the washer did not go in to the engine.....

This was about 3 hours and with luck i can put it back together in 6 hours

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## Spin

So you have a decent pipe and cam timing mods, any mods done on the airbox / fuel intake side of things?

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## yankee99

yes the airbox has a boss 175 snorkel which is larger then the original. Its available here for a couple 100baht. The box needs to be modified but it only takes a few minutes.



Remember when you do this mod the bike will run lean. You can use a couple of resistors i think 330ohm to jump the a/f sensor. I did this before i upgrded to a power commander.

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## draco888

nice work. how much hp or % increase do you expect when finished?

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## supernovadw

Good work and a good thread! It's great to share info.

It's ironic because this morning I was reading on the Thai Visa forum about a KLX250 the same which had a big bore kit and the guy's efforts to get it running well.

In all honesty I don't think a power commander is going to do the job, you will have to go for a fully stand alone ECU. API Tech (A Thai company) Make one which is what the other guy was using. If you can take your bike to Bangkok where they are based they can tune it on their dyno otherwise you can tune it yourself on your laptop or they can even do it remotely.

I will try and find the thread I was reading and post the link.

I am looking forward to doing some mods to my CRF 250 L. Just not as much available at the moment of course. I have a Ben 740 Exhaust and API Tech ECU On order for a start which should hopefully give some positive results  :Very Happy:  Long term I'd like to go for a big bore kit, aftermarket cams, CBR 250 Throttle body etc...

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## yankee99

> nice work. how much hp or % increase do you expect when finished?


Its going to be hard to estimate a exact figure. Stock hp is 18. With this mod and the others already done i am looking between 25-30 although 30 is a stretch.

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## yankee99

> Good work and a good thread! It's great to share info.
> 
> It's ironic because this morning I was reading on the Thai Visa forum about a KLX250 the same which had a big bore kit and the guy's efforts to get it running well.
> 
> In all honesty I don't think a power commander is going to do the job, you will have to go for a fully stand alone ECU. API Tech (A Thai company) Make one which is what the other guy was using. If you can take your bike to Bangkok where they are based they can tune it on their dyno otherwise you can tune it yourself on your laptop or they can even do it remotely.
> 
> I will try and find the thread I was reading and post the link.
> 
> I am looking forward to doing some mods to my CRF 250 L. Just not as much available at the moment of course. I have a Ben 740 Exhaust and API Tech ECU On order for a start which should hopefully give some positive results  Long term I'd like to go for a big bore kit, aftermarket cams, CBR 250 Throttle body etc...


I know many klxs running big bore 300, 330 & 351. They are all using the pcv. I have not found one klx running a big bore sucessfuly with api. The api is superior but its to complicated. I can not read thai and my verbal is limited. I can not be held hostage to a couple of tuners in bkk. The api is a lot more money then the pcv with half the support. Remote tuning is a joke right. How can one judge improvement? Seat of pants dyno? 

The crf250l is a good bike but as you say upgrades are limited. I dont think you will see a big bore but i may be wrong. I would recommend a radiator  guard as they are weak and vulnerable especially if you going off road. After you mod it get a dyno run and post the results. I plan on doing the same.

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## yankee99

So today did not go very well. I will upload some photos but dont have a lot. Basically installation is the opposite of disassembly. Started by painting the 300 cylinder. Thailand has hi-temp paint but no semi gloss black. Used flat black and it will blend ok.

 The new piston needed to be attached to the connecting rod. It has a pin and 2 clips to keep it [the pin] in place. I was nervous about these clips as they are small and not easy to insert. One clip was inserted on the bench. Then the piston was set on the connecting rod[arrow pointing forward] pin inserted then the clip. Wow i felt great it went smooth. I had all kinds of towels and rags in case it popped so i wouldnt lose it.

Next to install was the new cylinder with my homemade ring compressor. All the surfaces were cleaned with paint thinner. I havent seen any gasket removing spray here. Thinner worked surprisingly well. After 2 attempts with the ring compressor success. Now the head gasket and the head. This is a little more difficult as its a tighter fit. About 10 minutes of wiggling it went on. 

Great this is going to be a breeze. Little did i know what lies ahead........The cylinder and head are held with 4 large and 2 small bolts. The 4 large bolts have washers under them. Theses washer did not come up during disassembly. I basically didnt know they were there. When installing the 4 large bolts i saw them and noticed one missing. You guessed it the worst case scenario. I assumed it fell in the engine case when originally removing the head. At this point i have to stop and locate this washer. 

Off with the cluthch cover, brake lever, water pump cover, impeller, some brackets and finally the right side case. OMFG was i lucky the washer was right there and easy to fish out. I re-assembled and torqued everything on the right side. fyi i re-used the old gaskets and this may or may not be a issue.  I then torqued the head bolts installed the cams and cam covers. I then proceeded to my swimming pool.

Looking to be finished tomorrow knock wood .

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## draco888

Swimming pool plus beer probably the best option  :Smile:

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## Satonic

351 runs with a pumper carb, 330 and 300 PCV.

Between a friend and I we are very soon going to be offering a one stop service klx 300/330/351 upgrade for anyone that wants it (Bangkok).

Thanks for taking the time to share the pics Yankee99  :Smile:

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## yankee99

@satonic think thats a good idea maybe i will go to 330 one day.

when are you coming here to ride?

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## yankee99

Finished the bike this morning and its running great. I will update the thread after i rest.

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## Satonic

> @satonic think thats a good idea maybe i will go to 330 one day.
> 
> when are you coming here to ride?


End of the month I think, I'll email you when I know for sure.

Cheers

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## supernovadw

> Originally Posted by supernovadw
> 
> 
> Good work and a good thread! It's great to share info.
> 
> It's ironic because this morning I was reading on the Thai Visa forum about a KLX250 the same which had a big bore kit and the guy's efforts to get it running well.
> 
> In all honesty I don't think a power commander is going to do the job, you will have to go for a fully stand alone ECU. API Tech (A Thai company) Make one which is what the other guy was using. If you can take your bike to Bangkok where they are based they can tune it on their dyno otherwise you can tune it yourself on your laptop or they can even do it remotely.
> 
> ...


Good to hear you have it all back together and running well! The problem with the API Tech ECU Is as you as it is complicated plus unless you speak Thai completely fluently you are going to have the communication problems. As you said you could take the bike to Bangkok to get it set up properly on the rolling road and I reckon you'd have a perfect running bike if you did this. As regards the remote tuning it's not a joke, it requires you to plug the ECU in to your computer via USB and to have a wireless internet connection so you can ride it and tweeks be made whilst you are riding. I.e. Live mapping.

As regards my bike I'm going to go for an exhaust and ECU to start with, I wasn't aware of any radiator problems but thanks for pointing it out! I do a bit of off roading but nothing major. 

I would like to get a dyno run once it is done but I live in Laos  :smiley laughing:  I don't know anyone who even knows what a dyno is let alone there being one here in the country. I don't know where the nearest one would be to be honest? 

As for parts there isn't a great deal available at the moment as you have said, there is however a couple of big bore kits, one is made by Bill Blue (Same company that does all the KLX Stuff) And another one I found is made in Indonesia for the CBR250R which of course shares the same engine.

Eventually I'd like to do the following:

-ECU
-Exhaust
-Cam
-300cc Big bore kit
-CBR250R Throttle body
-Port and polished head

I found a CBR250R on a Thai website with similar mods and it was making 34bhp at the wheel which I find pretty impressive! I reckon it'd be a real little flier like this!

Anyhow I shall see how funds allow....

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## yankee99

^^^^Maybe api is doing it differently now. A guy in phuket was getting remote tuning from api. They were using teamviewer or something similar. I dont think he had a pc strapped to his bike and went riding while they were monitoring and making changes. As far as i know the bike was stationary and the changes were made. Unfortunately it never worked properly and i assume without being able to check the a/f it is virtually impossible. Unless they have a map of a bike with very similar mods. The PCv can be self tuned too if you get the auto tune sensor.

Keep us updated on api i am interested in the results..

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## yankee99

After the discovery of the missing washer the hunt was on. Lucky me i found it here.



The new 300cc piston nicely installed with my homemade ring compressor



Timing the cams is critical after dis assembly. Dont go buy my pics as my timing has been modified. If you look closely you can see the changes.



These are the damaged radiators from previous falls. I am surprised they havent leaked.





Before i start the bike i need to change the map from a 250cc to a 300cc. These were sent to me from a biker in spain. He has almost identical mods. He sent me 2 maps one for daily commute and one for racing. You can upload both to the PCv and use a external switch to go back and forth. I dont have a switch so only the racing map for me.

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## yankee99

I have changed the oil twice already and added about 100 kilometers. Looking in to the sight glass everything looks great. How does it run? Well for a thai klx it runs great. I cant give dyno figures but i can compare mods. Stock this bike is a 2 legged dog and cant get out of its way. After all the 250 mods with a 13/42 gear i could get the front wheel up by compressing the forks, sitting back and pulling up on the bars. It was a circus act for sure. Now i only need the throttle to wheelie it in first. In second it takes some circus tricks but still easier then 1st gear as a 250.

It is a pleasure to ride now and make me smile...

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## Satonic

Yankee99, how much diff did the cam mod alone make? Is it worth doing?

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## yankee99

> Yankee99, how much diff did the cam mod alone make? Is it worth doing?


yes its worth doing .... its a free mod with a nice power gain. If you look at my photo the intake is modded but the exhaust is back to stock. Before the 300 i had both the in&ex modded.   My understanding is if you go to 330cc the mod has no benefits.

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## draco888

> Originally Posted by Satonic
> 
> 
> Yankee99, how much diff did the cam mod alone make? Is it worth doing?
> 
> 
> yes its worth doing .... its a free mod with a nice power gain. If you look at my photo the intake is modded but the exhaust is back to stock. Before the 300 i had both the in&ex modded.   My understanding is if you go to 330cc the mod has no benefits.


Nice work. Do you have a mechanical background or just a hobby?

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## Satonic

> Originally Posted by Satonic
> 
> 
> Yankee99, how much diff did the cam mod alone make? Is it worth doing?
> 
> 
> yes its worth doing .... its a free mod with a nice power gain. If you look at my photo the intake is modded but the exhaust is back to stock. Before the 300 i had both the in&ex modded.   My understanding is if you go to 330cc the mod has no benefits.


Yes it's not recommended with either the 330 or 351.

I'll have a go at it then and report back.

Cheers

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## yankee99

> Originally Posted by yankee99
> 
> 
> 
> 
> 
> 
> 
>  Originally Posted by Satonic
> ...


thank you......no mechanical background i enjoy doing it and the real satisfaction is when the job is done and working correctly.

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## Golden Inn

> 351 runs with a pumper carb, 330 and 300 PCV.
> 
> Between a friend and I we are very soon going to be offering a one stop service klx 300/330/351 upgrade for anyone that wants it (Bangkok).
> 
> Thanks for taking the time to share the pics Yankee99


Please let me know when you are going to make the one stop service for the upgrade

Regards

Preben

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## Satonic

> Originally Posted by Satonic
> 
> 
> 351 runs with a pumper carb, 330 and 300 PCV.
> 
> Between a friend and I we are very soon going to be offering a one stop service klx 300/330/351 upgrade for anyone that wants it (Bangkok).
> 
> Thanks for taking the time to share the pics Yankee99 
> 
> ...


PM sent.

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