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Smoothing it our


chewy
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yea the 290 is far beter than the 250. 3 base gaskets and retard the timing and slow action throttle.done quite a few and it works.why change carbs etc when its already got one, nothing wrong with the one thats on it.

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Copey

me thinks you have a somewhat hotter / drier climate than the UK as you will discover shortly at the ssdt......

36 pilot and the mixture screw is 2.5 turns out, think thats about in the middle. If I go to a 38 then the bike will be too rich on a damp day at my favourite event ! Damp days are fairly common at this particular trial

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Copey

me thinks you have a somewhat hotter / drier climate than the UK as you will discover shortly at the ssdt......

36 pilot and the mixture screw is 2.5 turns out, think thats about in the middle. If I go to a 38 then the bike will be too rich on a damp day at my favourite event ! Damp days are fairly common at this particular trial

Actually it is a bit opposite, as with cooler high air density days one actually needs a bit more fuel to go with the denser air. It sounds to me you are getting in the happy range with the 36, as i figure it working good at the 2.5 out setting.

You seem the only gunie pig I have over there to try this as I have preached thus far in finding. Nothing says you must retain the setting prior to your final prep. But I want to see if things change at 38 and down to two(2) turns or so, mine was at 1.5, as this still effects the transition circuit at 1/16-1/8 throttle and if it gets too lumpy there you will know, if not, then you will be good and likely find as good a transition as I did, which may be optimum on what the Dell can actually do.

Seems many have not ventured even as far as you thus far in getting these things in a really good working range. Nothing I can simulate here on our fuel and conditions so rely on your input for others in pushing the optimums here.

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Am I that out of touch Cope coming to SSDT? good news... Just a bit of feedback for you Cope; fitted Boyenson 665 reeds today to my ST 250.. Using std/Sherco stop plates,result very noticable I can get better control of airscrew/bottom end running and am nearly happy with it.. It will now tickover at slower revs than one would want to ride it at)... still a big bang/lump occasionally using 35 pilot jet and 1 .25 turns out of mixture screw or it leans out and hunts. TRied messing with the timing by tiny increment either way and ended up back where I started . Only other side effect is the reeds sound like tappets on a BSA....most encouraged and gratefull for the advice so far. Let you know if smaller pilot jet and more air smooths it out.

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something doesnt sound right here.

Boyesen Reeds tend to make the bike run lean on the pilot, so on my 07 290 when I fitted them i had to go up a size on the pilot jet. So your bike Chewy should, all other things being equal, be running weaker than mine with std reeds.

I have a 36 pilot at 2.5 turns out and your running 35 at 1.5 with the boyesen reeds?

why is your bike not pinking ?

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you tell me;...They are all same but diferent?. I could make it pink by turning mixture screw 1/2 turn from right in but then it was hunting anyway and I could stop it by putting screw all the way in, it did say in the fitting blurb that the reeds would make it run richer on main jet and leaner on the pilot jet, it is cleaner/smoother at the bottom end but my feeling is to go a bit smaller and get more adjustment.

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you tell me;...They are all same but diferent?. I could make it pink by turning mixture screw 1/2 turn from right in but then it was hunting anyway and I could stop it by putting screw all the way in, it did say in the fitting blurb that the reeds would make it run richer on main jet and leaner on the pilot jet, it is cleaner/smoother at the bottom end but my feeling is to go a bit smaller and get more adjustment.

You aer working with fuel, not air on the screw, totally backwards, so fit the 36-38 range on pilot , should be in 2 turn range +- I would think.

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Hi Neo as you may have gathered I'm still trying to get max out of the Dellorto. to clarify the issue over air screw / mixture screw. I know which way to turn the screws on these different carbs but my line of logic with the Dellorto is that with the 35 pilot jet I can't get to adjust total amount of fuel metered by the pilot jet without practically or actually stopping the thing altogether so fit a smaller jet to get into a sensible range of adjustment. Testing on Sunday last was curtailed by one of our chaps falling off and breaking his wrist so we had to get him to hospital...there's always something eh?

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