I believe S1's can't have their ecm mapping changed because they ain't got one. But is there any other method of tuning that electrikery stuff.

Since Tubbs did an excellent up-grade the engine, the characteristics are certainly faster - at top end, but it has probably lost a little bottom end.

Can this be tinkered with - presumably on a dyno - to change it so it is lower in the rev range.

Put Sportster cams in it if you want bottom end!

Shuds, smash your piggy bank and get yourself a Crane single-fire ignition module.
Remember though, you won't be able to get one of these for three ha'pence and a bag of chittlings,.

Unless, of course, it's a very big bag of chittlings..........

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http://www.youtube.com/watch?v=Pbi5Ggmk ... re=related

I remember checking out crane ignition a while back and from what I could surf-out it didn't make a big difference. So it improves bottom end

........ I haven't got any chittlings, its just the way I walk - boom boom

I have a 42mm Mikuni and Crane H14 on my X1. You are welcome to give it a blast at East Kirkby if your going Shudders.
This is a polite genuine offer as I'm just about to comment on your video

ive done - in this order

mikuni 42mm carb
race filter
race headers and silencer
crane single fire ignition
screamin eagle 536 cams
nrhs 1250 big bore kit
along with US gearing

then get it all set up on a dyno, ideally by soneone who knows buells

what was the overall improvement like? and what item made the biggest improvement,i know there were other items in the equation but which one do you think was the best investment?

Without a shadow of doubt. IMHO, the biggest single improvement by a long way is gained by fitting US gearing compared to Euro gearing. I would say probably the next biggest improvement would be the suspension, but I don't really need that anyway at the speeds I travel at. (I have a Works rear shock fitted). The big unsung advantage of those strategies is that the bike's reliability isn't compromised.

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Try doing this to yer fueller...........

The old XL1200S "sportster sport" deliberately used twin plugged heads, single fire ignition and different cams to give a sportier sportster with oodles of bottom end even on stock pipes.

These models were comtemporary with the S1.

oh yeah... and brakes and suspension were fitted as standard too

Thanks Spook, but East Kirby's too much of a hike for me - on a s1.

No one has actually said the crane single fire module dooby makes a noticable difference. My interweb search can't find any dyno read outs either.

The cheddar gorge video ? - too many civilians about to go mad - sounds good though don't she I will try again one early morn and try and get that bullitt sound

The NRHS site has lots of plots to compare different mods.

If you want more bottom end, you need to identify what the problem is. Is it mixture (needle) or ignition (change the timing) or volumtric efficiency (change the cams, exhaust, inlet length [you have a very short inlet tract - try making it longer])?

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08 Specialized Langster

Presumably, Crane branded sparks are indistiguishable (spelling?) from anybody else's brand of sparks?

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Try doing this to yer fueller...........

Depends what time they arrive

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08 Specialized Langster

Ah, but time is relative, not absolute.

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Try doing this to yer fueller...........

not only does the crane single fire make a notiable difference, it allows finer tuning of the ignition system you neeed to get the most power out of the bike

mines now putting out 101 bhp - dynoed it 500 miles afgter big bore went on
its now loosened up more, so will be going back on shortly

its no good throwing money at it and then not getting it set up - I got an extra 12bhp !! during adjustments on the dyno (torquetune 07976 961442 notts)