WK400 owners thread.

[Scotriders]

The pipes from the engine should connect to what I'm guessing is a clean air system which wasn't connected anyway so I've removed the whole lot. Gonna blank off where pipes came from barrel but I do have an electrical plug which was attached to the clean air system which I'll need to work out if it should be open or closed.
Suspect the oil leak from an air pipe is due to me topping the oil up when the engine was cold so gonna drain everything and refill to correct levels.

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[Hugh]

Greetings,

I don't think that it would be a good idea to totally blank off the breather as the engine crankcase system has to breath as the air inside heats up and cools down, failure to do so could cause excessive crankcase pressure leading to excessive oil consumption and/or blown oil seals.

I do n't know why the pipe would have been disconnected but I would try to clean out the 'collector' box, which catches the oil from the emulsified air, and securely refit the original pipe. If the previous owner had been overfilling the level then probably the excess pressure was filling the collector and leaking. The correct level is essential, never make the misguided mistake to think that over filling is not a problem, it is better to run slightly lower than maximum in my experience.

TTFN

Hugh.

[netsonic]

The disconnected hose is part of the clean air system, pulses air into the exhaust ports to allegedly reduce emissions I guess and meet regulatory standards for sale in the EU

Its not part of the crankcase breather on this bike as that's in a different place. When the bike was originally built with a carb it never had all this stuff so removing should be possible but my guess is you will get a permanent ECU error....good luck

The oil leak as you say is likely to overfilling with oil, its a dry sump so should be checked with a hot engine, overfilling will make the oil leak out the head gasket, I fill mine with no more than 2.1 litres never leaked to date, I think its been mentioned on this thread a few times

[Scotriders]

So I've removed the whole lot of the clean air system and as said by netsonic it caused the red light on the dash to come on. However I shorted across the plug and light appears to be staying off (will need to test ride it to confirm.

My latest problem is the exhaust system, both silencers have cracked. Anyone else had this problem?

Anyone know of a reasonably priced aftermarket system to fit?

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[netsonic]

Crikey looks like some tin worm has assisted, not sure but it may be an aluminium plate pot riveted on in that area so could be fabricated

This guy in the Ukraine has done some major mods including removing the two exhaust and replacing with a new alternative, may give you some ideas unless you buy a new standard pipe or know a good metal fabricator, let us know how you get on

http://geon-club.com.ua/forum/viewtopic ... &start=325

[Scotriders]

Last couple of day's tinkering.

Exhaust off was easy, decided I'm going for new headers too but nuts didn't look like they were for loosening so lots of heat on studs and thankfully all four out without a problem.
I've ordered stainless headers for an XR400 which should fit straight on, also ordered a lambda sensor eliminator for it. A Lextex stainless can and link pipe which will need bit of adjustment to fit.

Valve clearances set, ordered new timing cover as the head came off when replacing it.
Eventually got the TPS mounting screw loosened (had to dremel a slot in it) my reading came up as 0.65 (which could explain some of the issues I've been having) set it to 0.74.

Drained the forks and put fresh 10W fluid in them.
Moved the reg/rec to the bar on the left under the tank, which free's up a fair bit of space where all the wires were crammed under the seat.

Engine oil and filter changed (only 2.1L)
Spark plug cap replaced with a straight one like on the XR250 as the wee angled rubber one fitted wasn't for coming out and I ended up ripping it too bits getting it out.
Plug was black and sooty and obviously some oils been leaking onto it too. Changed air filter.

Made up a couple of plates to go over where the clean air pipes came out the head.



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[netsonic]

that's some serious mods, I also looked at the xr400 header but as it had no lambda fitting never pursued it, interested in more detail on the parts especially the lambda sensor eliminator and how it all fits together, and ultimately if it runs better

Removing all those clean air bits tidies up the engine area really well...……..very nicely machined blanking plates may I say

[netsonic]

if you get a moment could you post a picture of the plug or plugs you shorted after removing the clean air bits as I may try this for starters

Many thanks

[Scotriders]

if you get a moment could you post a picture of the plug or plugs you shorted after removing the clean air bits as I may try this for starters

Many thanks

Just the one plug left after removing all the clean air parts.
My initial thought was to just cut the plug off, join the ends and insulate it but didn't know if it would work (still don't until I get the new exhaust on and take it for a ride)
As you can see I just tinned both ends of a short piece of wire then pushed them in across the two connectors.
Taped up the plug with insulating tape.
Tucked it up beside the connector on the right side of the top frame tube.


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[EdwardCollings]

Hello

Firstly thanks to everyone for posting all this great information, I picked up a WK400 Trail myself a couple of weeks ago and what started out as just fixing a weeping oil seal and a crack in the exhaust just like Scotriders has morphed into a project very similar to Scotriders who's ideas I have borrowed!

Its taken me a while to get my account activated as I'm a pleb with I.T.

So far due to stupidity on my part and an if I'm going this far I might as well just do it I've done the following and have some photos

Fork re-build with new seals, inner and outer guides (one fork was missing the inner guide completely and being an idiot I trashed my outer guide) also new oil

New standard headers with the internal welds ground back to really open up the head of the pipes (I have taken a photo of my old headers so you can see how large the welds are) though wish I had read Scotriders post and just bought XR headers for the same money

Delkevic 350mm carbon can with home made link pipe. The can was pinched from my Honda Hornet

New EBC rear pads

On the list to do

Tank breather Mod
O2 Delete

And put the bike back together once my wheels are ready as they're having road tyres fitted

Scotrider have you had any luck removing the clean air system and have the bike still run fine?