Installing a 3 gallon IMS tank on EFI Kawasaki KLX 250. A DIY guide.

Dec 4, 2012
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Mine arrived in the Thailand on the 1st, tracking says it's with customs in Bangkok. Anybody got any ideas on who to call?
 
Oct 20, 2012
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[sup]I need to get this done too Brian mines woefull since I had the 331 fitted
where do you order and can you give me a heads up on buying/fitting prices
thanks fellas[/sup]
 
Dec 4, 2012
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I paid $330.10 including postage, it's just cleared customs and should be delivered in next couple of days.
Import tax and VAT may cost as much as 5000baht but I'll let you know.
 
Oct 20, 2012
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That tank looks great Jim, you have really tricked that KLX out, ide be too scared to drop it.
Thanks for the advice on the tank
 
Mar 30, 2010
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sorry guys.. missed the replies to this thread.

Didn't pay any tax this time.. showed them all the last docs and pictures of the destroyed tank.
Just had to complete some forms and walk out of the Bangkok Mail Centre..

So far all good.. took it for a session with Xtreme Enduro Pattaya..
Still on one piece and no leaks etc.. so looks good to tour with.

Last time when the first faulty tank came in.. I paid 3,000 baht tax I think it was.

Cheers
Brian
 
Dec 4, 2012
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No one else had a problem with missing fuel suction fitting? Mine was either never supplied (doubtful) or was taken off and lost by guy who did the coating (likely). I measured the hole and decided it was 3/8 npt. Turns out npt fittings are measured by ID not OD. Am back in UK just now and have bought around 10 different npt fittings in the hope one of them will fit. If someone tells me it is not an npt thread I will throw the whole bike in the bin.
:mad:
 
Dec 4, 2012
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WP_20141110_13_09_21_Pro_zps90c689fe.jpg


Hope one of these fits.
Also fabricating pair valve block off plate from 4mm aluminum.
 
Apr 3, 2011
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Just noticed this topic, happy news such a fuel tank exists finally! I was thinking about upgrading to 300 some time in the future, but with the bigger tank available might just go to 331.
Jimmy, I recently made exactly same looking block-off plate, what do you reckon about the hole in the head leading to that valve, should it be plugged up by something? Are you gonna install the old reed valve with the block-off plate on top instead of the stock plate with a hose fitting, or just the block-off plate instead of the whole stock setup? I still haven't put my bike back together, but gonna do it next week. I wonder if the ECU gonna indicate an error code, because the air switching valve is in the bin and it's connector is disconnected. I wonder if that connector needs some resistor connected to simulate the air switching valve present?
 
Apr 3, 2011
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TonyBKK;301792 wrote: Congrats!

Your tank still needs to be able to vent as the fuel heats up and expands and cools and contracts.

I bought a bunch of these cheapie dirtbike tank vents off eBay- gets the job done!

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Tony, does yours have a one-way valve inside? I got a pack of very similar looking valves from eBay (yellow anodized color and clear hose), and they are actually just a mushroom-looking head with an off-center vent hole at the bottom, no valve inside. Gotta be careful if dropping that bike, I guess.
 
Dec 4, 2012
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Finally installed tank.
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Was a bit of a pain, after finding a fitting that worked it leaked. PTFE tape and a seal all good now.
For ditching all the clean air stuff I plugged all connections, 2 on air box and one on throttle body and bolted home made plate directly to head using old gasket.
Then measured resistance of servo valve, 28.5 ohms which worked out to two 56 ohm resistors in parallel.
WP_20141118_21_00_57_Pro_zps5d7788aa.jpg

Soldered them in and no FI light.

My shrouds were real hard to line up, had to trim mesh and loosen everything but got there in the end.
Overall happy but the carbon effect ain't great (water transfer print) and had to make up IMS sticker in green.
Here's some photos.
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WP_20141123_17_36_49_Pro_zpsc5cf50d1.jpg

WP_20141123_17_37_03_Pro_zps9d0a3b6c.jpg
 
Dec 4, 2012
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jimbobs;302859 wrote: Thats the best looking KLX ive seen, that seat looks fantastic is it an aftermarket?
Thanks.
Not finished by a long shot.
Seat is made buy company called Sargent in USA. Cost a lot with import tax and shipping but very comfortable.
 
Apr 3, 2011
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jimmyklx;302857 wrote:
For ditching all the clean air stuff I plugged all connections, 2 on air box and one on throttle body and bolted home made plate directly to head using old gasket.
Then measured resistance of servo valve, 28.5 ohms which worked out to two 56 ohm resistors in parallel.
Soldered them in and no FI light.
What did you use for home-made plate? I made one using 3mm flat aluminum, and then found out the clamping force of two bolts is not enough to hold the gasket tight enough against the head at the two corners farthest away from the screws. Either that or my flat piece was not entirely flat (even though I did sand it on a sanding block)... Anyway gonna look for thicker aluminum (I heard 4mm and 6mm were mentioned by two different people) and make sure it's flat.

The resistance sounds about right, per the manual standard resistance is 24-28 Ohm at 20C ambient temperature. I'm concerned with durability of the resistor replacement, though. There's at least 12V, probably around 14V during bike's operation, applied to this air switching valve. Basically that's 500mA current flowing through those resistors, that's a lot. This is 7W of power the resistors should dissipate (if always on). Resistors on your picture look like typical small-wattage one, 1/4W or 1/2W if I'm not mistaken. I don't know for how often and for how long this valve receives power - is it in short pulses or does it stay powered for significant durations under some riding conditions. I just figure if there's 500mA flowing through these resistors for any significant amount of time, they will overheat and burn out pretty quickly. I'm yet to do the resistor mod myself. I'm wondering how the ECU tests the valve on start-up. If it's just testing continuity of that circuit, maybe it will be satisfied with a higher value resistor. For example, if a 10 kOhm resistor would be enough to avoid FI light, that would be a safer choice.
 
Dec 4, 2012
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Heilong.
I posted too soon, after around 3 minutes FI light came on. I've not had a chance to check but it looks like you're right. I didn't consider the power aspect.
For the plate I used 4mm and it seems to do the job.
I've got to go to work so it'll be 4 weeks until I confirm. In the meantime I'll be looking for some higher wattage resisters.
 
Apr 3, 2011
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Sounds like maybe your resistor burned up after 3 minutes, breaking the circuit. Simplest temporary measure would be to just plug in the original air suction valve, with no hoses connected to it. It's rather heavy, though. Being an energy saving kind of guy I really don't like the idea of wasting 7W (or around) of alternator's output on just heating the environment with some high-power resistor (I think in this power range it has to be a chunky ceramic resistor). There's gotta be some smarter way around it...
I wonder what other people who removed the "smog crap" did. I've read a big discussion about that issue, and nobody mentioned any details about the electrical part of the blocking off. Most of the folks had the carbureted KLX,though.

Yesterday I was out in town (Pran Buri) looking for >= 4mm thick aluminum plate, and my search came up empty. There are a bunch of metal shops who sell steel and stainless steel, wherever I asked for aluminum, they pointed me to shops dealing with windows, which only have various aluminum profiles in weird shapes and very thin aluminum (for making windows, obviously). Couldn't find a shop selling plate or sheet aluminum in various sizes. One metal shop had huge sheets of aluminum, which they said they can't cut to size (have to buy whole sheet), and the thickest one they had was 3mm. Got a piece of 3mm stainless steel plate, but I'd rather use aluminum... Any advice on where to go looking for it in a Thail town? Next thing comes to my mind is Chinatown area in Bangkok...

PS Jimmy I put my old cylinder and piston back and hope they will last for a couple of months, I'm really interested in your old cylinder&piston when you get your big bore kit. Thanks!
--Gene
 
Apr 3, 2011
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Regarding the air switching valve resistor - I've tested various value resistors and it appears even a 47 kiloohm resistor plugged instead of the air switching valve makes the ECU satisfied - no FI red light.
After doing these tests, I cut off the air switching valve connector on the wiring harness and soldered in a 10 kiloohm resistor in it's place, then cover the whole thing with adhesive-lined heatshrink tube, and tucked the whole thing in the sheath of the harness which continues to the horn, then wrapped with tape. So looks very neat, nothing reminds of connector that once was there. Today I finally got the bike completely together, it started right up, did a hard break-in for the new piston and rings, rode hard for about 35 km - still no FI light. By my calculations, the power dissipation of the 10 kiloohm resistor will be less than 25 mW, so the 1/4 W rated resistor I used should be more than enough.