Crofter985'S KLX650C supermoto build

[Sandblaster]

Is this bike going to be in the next mad max movie?

You could black your bike out then dress up like one of these guys



You would be a Star over night!

Just put this gal on the back and ride wheelies around town..

[Crofter985]

That's uncanny Mike, that's almost identical to our traditional Shetland post apocolypse clothing. Here is an example......

[Sandblaster]

Hilarious

[Crofter985]

Just thought I would put this picture up
Of the fuel pressure sample point. This bit sticking outside the frame screws out and can be plugged by a 1/8bsp plug. It also makes nice chunky connections for the fuel hose, so no need to disturb the banjo bolt on the side of the FPR, which if you remember leaked to begin with, new copper washers and a bit of sealant sorted that but it's not an ideal connection for multiple connect/disconnect but the fittings on the fuel pressure point are.

So the new float valve seat arrived, so off to the shed I went. Put it in, which was not a big job.... Disconnect the water/meth controller and the fuel pump, unscrew the pressure/vac feed and the fuel feed to the pressure point, then unscrew the dump valve pipe from the carb stub and the four bolts holding the plenum/subframe on, take off the jubilee clips on the plenum inlet and plenum outlet then pull off plenum and rest it on the back wheel. Then two m6 socket head screws holding the carb on and it's out. I was really pleased this all seemed so easy. I can only guess at how many times I might have to do this before this thing works properly.
So I fitted the valve and time for another go.
So turned it over a bit but no dice, then saw fuel dripping out the exhaust gasket as before. Shit, so the valve is leaking again. Why? It's meant to be a pump valve??
I'm guessing the pressure is still too high. So to help with that I have now ordered a +15psi/-15psi gauge so I can read it at the low pressures better and hopefully stop this leak past the float valve. I switched the pump off and tried starting it (oh yeh, I also noticed the main jet was not tightened properly so tightened it in the threads so I wanted to see if it was more willing to run because of that), it wasn't that keen but then there was a lot of petrol in the engine so I kept on trying and it went but only for a few seconds, with a bit more messing about it did run for a bit but showing 14-14.5 afr so a bit lean. All this does not mean much, I have to establish the fuel pressure better with the new gauge and take it from there. There is fresh petrol in the tank, fresh plug in it, there could though be a blockage in the pilot jet. Next time I get home I will strip the carb before I try again.

[Sandblaster]

Reminds me of when I put a 50lb fuel pump on my Chevota (Long story). Fired it up and took a ride... Ah didn't last long before the engine stalled and fuel was all over the place. I don't remember what the final number was, I think it was around 7 lb... A bike carb fuel valve has got to be a small fraction of that. I know you'll find the sweet spot

[Crofter985]

another thing I forgot to say about was when I was turning the bike over, the vac signal is so strong, the cheap boost/vac gauge needle just flies around everywhere!! This will be being transmitted to the carb through the float bowl pressure reference. Perhaps that is what is making it lean at idle?? It's a 50 pilot jet that's in so I have ordered a 60 and also I have also ordered a one way valve like the kind you would find on screen wash tubing, my thinking on that is the float bowl would never normally see vac, if I isolate the float bowl from vac it might cure the lean idle, it also might throw up other problems, it would go on in line between the tee and the carb like in this pic.

It's a 180 main that's in btw

[Sandblaster]

Hmmm... Your right, normally there might be a very very slight vacuum in the bowl area but no where near what your inducing.
Wow... It just continues to boggle the mind...
You need one of these symbols next to your ID

[Crofter985]

I am trying to go through this methodically, first things first and all that, so fuel pressure issues needs to be sorted, it's difficult to get a gauge that reads low well so the gauge I have ordered that reads into vac should give me a better handle on what's happening and what pressure is there.
The idle AFR of 14-14.5 is a strange one, the choke was on too. It could be a blockage, it could be something else??
I have about 2-3 weeks work now so plenty of time to think it through some more.
Another thing ....... I forgot to mention was the gasket between the carb and the head was sticking into the Inlet so I trimmed it when the carb was off.
Yeh lots of things, the shed is like a war zone, I need to have a tidy up, get the Klx on the roller, fix the fan to the dyno and put the cooling system on the Klx. So the story goes on.

[Sandblaster]

I've got the word out with some pretty crafty fellows about this issue.
It will be interesting to see if they have any insights to share.

[Sandblaster]

A master builder I know said that you would most likely have to build a box around the carb.
I may have mentioned it before, I just can't remember.
But I have heard the same thing from a few other forums over the years.