9 replies to this topic

[bobtlr]

Hey,

my sherco's (2007 3.2) carb started to lose a lot of fuel out the little tube that comes out the carb (overflow?) some peoply told me i should fit a longer tube and route it over the carb to stop the dripping? is this correct? and will my bike not flood then?

float is set at 19 mm
pilot jet 48
main jet 120
air 3/4 out

ps the bike starts badly now wen hot, cold start is no problem (it did start ok before)


regards bob

[copemech]

This sounds as though the level is getting too high, either through sticky floats or some crap in the needle and seat. Wayne had reported minor plastic pieces probably from the tank effecting the jets even.

I think I recall a setting on the 45 pilot as well, would need to look back through the posts for to be sure, yet I would not think there would bee that much spillage unless the levels were too high for a reason! Although I do realize they slosh a bit. Look back through the posts on this.

One of the other members suggested blocking the overflow for this reason, but that may not help if something is wrong.

I am not sure about the orientation of the bowl vent tube in the side of the bowl on the 4T, but on the 2T, they are too close to the muff and will shut off if there is a hose on it. Can clog with dirt, even with no tube. The drilling out of the left vent may be advisable if not done. I do not have one to look at, so unsure.

[bobtlr]

hey,

checked the floaterneedle idd it was dirty,
changed air screw to 2 tunrs out bike starts perfect now and idle speed is verry constant

regards bob

[copemech]

Hey Bob,

Good on you then, but I doo still think the 48 pilot may bee a bit much?

All the reports I have seen suggest that these carbs like to run in the .5- to 1.5 range on the screw to optimize their adjustment range and sensitivity, which does change a lot and require adjustments with temps and such. FYI only, as good is good!

[bobtlr]

hey,

i agree have orderd a 42 and a 45 pilot jet to try, but for now i hope it will work

regards bob

[Wayne Thais]

2 turns out seems to be very lean, I am running 1/2 turn out on my new 09 and on my 08 I usually ran it at around 5/8 turn out. Sherco recommends 1/2 - 3/4 turns out. If you at 2 turns you may be a bit large on the pilot jet. However if it is starting and running good I would probably leave it alone.

Wayne

[copemech]

The more I think about this, the 48 may still work well as stated given the cooler winter temps and things could change as the weather warms.

Both the carb and the 4T are somewhat sensitive to these things! And as you may already be on the outer limits of the airscrew working range, well you get the drift!

As the K carb has no pre-screen(banjo) filter such as the Dellorto, an inline device may be recomendable? As the pre-screen in the tank(fuel valve) may not be up to the task. But on the same token, would be excess if your fuel supply is kept clean and good!

A thing of some signifigance to mee of late has been the condensation developed in the plastic storage tanks of premix fuel.

I have gotton to the point that I can no longer just assume there is no water or other "stuff" so as my jug gets low, I do not pour off the bottom into the bike without first inverting the can into a cleaned and dried 2 L or so cleaned and dried clear pop or juice bottle to let sit and settle!

I think there is another potential problem with our alcohol laced fuel and fallout of the alcohol induced emulsified mix!

You might be surprized to see just wot settles out of your can!

After settling, you can pour the rest back, except off the bottom! Hopefully your stuff is clean, keep it so!

Edited by copemech, 28 February 2009 - 04:16 AM.

[bobtlr]

hey

idd i've noticed that with modern fuel (98ron in belgium) there is more siment in my fuelcontainer, bought me a funnel with filtermase to fill up the bike.
i will try the smaller pilotjet when i get it mayby bike runs fine on 1/2-3/4 turns out then.

regards bob

ps wat pilot jets are you running on?

[copemech]

bobtlr, on Feb 28 2009, 11:27 AM, said:

hey

idd i've noticed that with modern fuel (98ron in belgium) there is more siment in my fuelcontainer, bought me a funnel with filtermase to fill up the bike.
i will try the smaller pilotjet when i get it mayby bike runs fine on 1/2-3/4 turns out then.

regards bob

ps wat pilot jets are you running on?

Although I do not have the 3.2 4T, the Kiehin that I do have for the 2.9 runs the same basic jetting and such. Same principles apply and I still think our alcohol induced fuel is not as good!

I have a couple more ideas, but I do not have one to play with! Volunteers?

Edited by copemech, 01 March 2009 - 04:27 AM.

[bobtlr]

hey ,

had a trial yesterday and the bike went fine (just cold starting is a bit of a problem now, never had that before)
idle is ok bike starts good no more fuel dripping out bit of black smoke and sometimes a flame on the overrun (but that is normal for ths bike says the importer)
I had a go on a mate's 2008 sherco 4t and his bike is a lot smoother. Mine (2007) is more agressive and revs higher also neerly no difference between the 2 mappings on my bike, the 2008 has more difference between the maps, have to say my bike was the importers own bike and he is a top rider the bike is "addapted" for his riding style.

is there a difference in power and power delivery between 2007 and 2008?

regards bob