A bit boggy - cold weather???

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storkfoot
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alanscottj wrote:
storkfoot wrote:Have a look at the air/fuel graph on your dyno printout. It may be that Readspeed left the jetting at the top end a tad rich. Then, when you get the really damp air that we have had in the last few days, it is making it too rich.

https://fbcdn-sphotos-g-a.akamaihd.net/ ... 5ed463294f
They haven't given you an air/ fuel readout unfortunately. If it's still happening, drop your main jet and see if that improves matters. But, obviously don't go hammering down the bypass at full throttle for mile after mile if you do :-)
mick1
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What's your plug like ? Might help to do a few chops at different throttle positions.
dave411
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Marty ULC wrote:Carb icing?
Thats what I thought.
Donnie
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mick1 wrote:What's your plug like ? Might help to do a few chops at different throttle positions.

Yayyyyyy some sense!

Back to basics, do a plug chop at full lumpy throttle. Get it warmed up, find a bit of road where you can sustain full throttle for about a quarter mile, kill engine and clutch in at the same time and coast into layby, check plug colour then tell us what it is.

better still, post a photo, but one in focus rather than a blurry timbo shot!!
Donnie.
alanscottj
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Donnie wrote:
mick1 wrote:What's your plug like ? Might help to do a few chops at different throttle positions.

Yayyyyyy some sense!

Back to basics, do a plug chop at full lumpy throttle. Get it warmed up, find a bit of road where you can sustain full throttle for about a quarter mile, kill engine and clutch in at the same time and coast into layby, check plug colour then tell us what it is.

better still, post a photo, but one in focus rather than a blurry timbo shot!!

Will do one tomorrow - I have a feeling I already know the answer - running too rich at WOT.

Once I know for sure, i.e. after plug chop tomorrow I am thinking of dropping the main jet (currently 108) and re-using the power jet that I have fitted (currently turned off) to give it the extra juice at full throttle, this will hopefully sort out the richness in the lower gears as well.
Lambretta Series 2 Rat - RB260, SuperTourer, Cyclone 5 gearbox ๐Ÿ˜Ž๐Ÿ‘
alanscottj
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Dropped from 108 to 104 tonight, running much better, especially in the lower gears, much smoother. But, with the power jet on half a turn it gets boggy again. So, my debate is now whether or not to drop it further (100 probably) and have the power jet on or to leave as is, 104 and no power jet. I could always go back to 108 when the weather changes again.

Any thoughts?
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Chris in Margate
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All those "add- ons" don't make an ounce of difference to your ignition circuit; conpletely separate.
Engine should run better in colder weather.
Start with basics; check plug colour, maybe try another.
Is choke plunger sticking?
alanscottj
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Chris in Margate wrote:All those "add- ons" don't make an ounce of difference to your ignition circuit; conpletely separate.
Engine should run better in colder weather.
Start with basics; check plug colour, maybe try another.
Is choke plunger sticking?
hi Chris, Readspeed set it up a bit rich, plug colour was quite dark. As I've said above I've dropped it from 108 to 104 and it seems better. Not had chance to try her out proper yet ;)
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coaster
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I still think you need to be a bit cautious, the 'damp' weather might be causing it to run rich but if the temp drops significantly, it WILL run weaker and if you've leaned it off too much you could end up holing a piston. Not a problem if you don't ride in the winter though.
alanscottj
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Just spoken to Jerome at Readspead and he talked me through how he had jetted my scoot and how he has set it up on the safe side and how this affects the top end. In a nut shell I can drop a main jet or two and see what it's like but obviously I will have to be cautious and careful. Going to try a 106 and see how that works. Top man Jerome, really went into detail and was more than hapy to help. Thanks for everyones input on here too. Every day is a school day!
Lambretta Series 2 Rat - RB260, SuperTourer, Cyclone 5 gearbox ๐Ÿ˜Ž๐Ÿ‘
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