Jet kit for XT600 e 4PT

[drumnagorrach]

Thanks Chaps .
A bigger pilot jet , 52.5 has cured the backfiring . I dismantled the carbs this evening ,all diaphragm's are fine ,float bowl has been butchered ,cap screw blocking off the float setting port and a blanked off hose on the outlet . Carb stub O rings are hard ,I would have changed them but the O ring groove has four equally spaced indentations ,preventing an O ring of the right size going in ( WTF ) Made expanded ptfe gaskets .
My main jet in the primary carb looked like 180 ,standard is 130 ,could I have misread ? would it be miles too rich at 180 ?
So far ,very happy with the feel and sound of the bike after this evenings fettlin ,just wondering about the main jet .
Cheers
Lee


Also got the carbon can on ,sounds loads better than the arrow with the welded on end , going to cut the end off the arrow

[philb]

I have the same problem as you, hunting at steady throttle & the odd 'pop' on the overrun, (the hunting was winding me up over the past week), so I took the carb off tonight and gave it a good clean. (There was some really fine 'silt' in the bottom of the float bowl, so I stripped the carb totally).

Small Diaphragm on the side was okay, but the brass plunger which pushes against it needed a good work out / clean out with carb cleaner. All the jets / nozzles were clean, but washed 'em through anyway with carb cleaner, blew them through with compressed air then put them back in.

Rebuilt the bike, took her out tonight, she runs a little better/cleaner but she still hunts at a steady throttle, but not as bad as before.

Anyway, I just ordered a XT600E Sigma Kit from the States (£39 inc postage). (My XT has: Std Airfilter & AirBox, Predator S/S Exhaust system).

Phil

[philb]

Received the Sigma Jet kit the other day, fitted it to the bike and it runs a lot better, no hesitating and seems to pull stronger too throughout the rev range.

For the tightwads (and some of the UK ex-pats amongst you) I have measured the main bits and pieces supplied so you can make your own kit up.

So, here are the bits for the 4PT XT600E...

It does say in the Kit instructions to do one modification at the time then test it works (But the carb is a bastard to fit & remove so I did it all at the same time, but I did not drill the CV Main Jet straight away, I took that out on the bike after a blast/test ride on the road).

Clean everything before you start and clean everything when its apart, blow all passageways with carb cleaner & compressed air.

Remove the needles from the slides. (LH Carb is fiddly ).

With the CV needle removed, Drill the CV Carb Slide with the 2.49mm twist drill. (Remove all swarf from the Slide).

If the both the carb needles have a 'E' clip, move the 'E' clip to the second notch from the pointy end. (to raise the needle). DO NOT use the shims!

If the needles DO NOT have 'E' clips fitted (i.e No Notches on the needle to raise/lower the needle in the slide), use the Nylon / Metal Shims. (Use two (2) Metal shims under the needle clip to raise the needle. Make sure the needle seats properly inside the slide body, if it doesn't use one (1) Nylon Shim instead.

Change the pilot jet for the larger size (52).

Change the LH Carb Main Jet (130, 135 & 140 Jets supplied with kit, I choose the 135).

Air mixture screw was screwed fully in and then backed out three (3) full turns. (Starting point).


Nylon Needle Shims (One per Carb)...







Metal Needle Shims (Two per Carb)...







Twist Drill for CV Slide (Kit Size #40)...





Main Jets for Non-CV side of the Carb...


Pilot Jets for Non-CV side of the Carb...



CV Main Jet Drill (#55)...


CV Main Jet Drill (#56)...



Rebuild the carb and refit to bike.....

Start her up, you may nedd to adjust the tickover ( I did).

Take it out for a run to get hot and up to temperature.

Air mixture screw was then tweaked until the fastest tick over was achieved.

Took it out for a longer run, it seemed to need more fuel at the top of the revs, so I took the CV Main Jet out whilst the carb was still fitted (Use a No. 6 Flat Bladed bit & a 6mm spanner & loosened the oil pipe from the top of the cylinder head for easier access). I drilled the jet out (using twist drill #56, 1.18mm) and refitted the Jet.


Hope this helps!!

[philb]

Here are the Jet kit fitting info sheets.....





Enjoy!

and one for Mezo

[Mezo]

Hey, sheep shagger?

Good info there Phil.

Mezo.

[Northern Jock]

Thanks Chaps .
A bigger pilot jet , 52.5 has cured the backfiring . I dismantled the carbs this evening ,all diaphragm's are fine ,float bowl has been butchered ,cap screw blocking off the float setting port and a blanked off hose on the outlet . Carb stub O rings are hard ,I would have changed them but the O ring groove has four equally spaced indentations ,preventing an O ring of the right size going in ( WTF ) Made expanded ptfe gaskets .
My main jet in the primary carb looked like 180 ,standard is 130 ,could I have misread ? would it be miles too rich at 180 ?
So far ,very happy with the feel and sound of the bike after this evenings fettlin ,just wondering about the main jet .
Cheers
Lee


Also got the carbon can on ,sounds loads better than the arrow with the welded on end , going to cut the end off the arrow

Hi, got similar issues with my XT, rough slow running which I think must be the pilot jet (new exhaust fitted). So I backfired my way round Europe for 5000 miles recently but need to sort it. Struggling to find a pilot jet size 52.5 - any suggestions of where to get?