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bike nut
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Discussion Starter · #1 ·
hi im looking for piguglyshandydrinker and his wealth of knowledge on transalp fueling systems :thumbright:

he is some what of a legend on other sites :thumbright: and this one

basicly im thinking of getting new front exhaust pipes to remove the hevey standard item and improve the generaly flow and keeping the original end can for now.

what i would like to know is a few things

should i remove the pair system? - how much does it change the fueling?

rejetting? - is it needed?

iv gone through all the other posts on this subject i think the general opinion was to leave the airbox alone with standard filter??

basicly whats the best way to set my bike up, if i get the new front pipes will i need any other changes to make them worthwhile?

all the work i can do myself so that is not a problem

many thanks :p
 

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Hi,
I guess it depends on what you are trying to achieve, there appears to be little gains in power by doing the various mods, 2hp max, you will gain a bit better throttle response and a bit better economy.

Basically, the bikes run a bit rich as stock - this knocks power, throttle response & economy.
Expect an improvement rather than a transformation.

Removing the PAIR does nothing for engine running/mixture or power but simply removes a bit of clutter & makes for simpler removal of the airbox for future - a couple of wellnuts tightened into the stubs on the rocker covers and in the bottom of the airbox does the trick pretty well.

Removing the cat alone gives a noticeable improvement in throttle response in the low - mid revs but the dyno shows it to be a miniscule improvement!

If you have money burning a hole in your pocket & want good looks fo for aftermarket headers, the budget option is to chop the cat off the stock pipes & get a local fabricator to weld a plate over the hole - £10 - £20?
Which effectively does the same job.



I have found that fitting 125 main jets instead of the 132's gives about 1-2 hp more through the rev range and an improvement in economy & throttle response.

They are about a tenner for the two jets from David Silvers (I can get the part number if you want it).
To change them you need to take the carbs off, a pretty easy job for a competent DIYer - tie it in with a valve check & plug change when you are there.

I am happy with this set up and have good fueling throughout the revrange.
There are other ways to achieve similar results, like holes in the airbox, K&N/foam filters & dropping the needles - they need machining to lower them, they seem to be a bit more hassle/more expensive & give less certain results - I personally didn't like the induction noise from the drilled airbox.

One final point - not all bikes will respond the same to similar mods, it's always worth going for a dyno run after to check that the fueling is ok (but, generally if it feels 'right' it probably is right).

I hope that this helps, if you want any more info, just give us a shout.

Phil
 

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bike nut
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Discussion Starter · #4 ·
:thumbright: many thanks some good stuff there

just wanted the new front pipes to loose some wieght and gain some looks :cool: and also increase the throttle response

i no any changes arnt going to turn it into a fire breathing monster

Do you still run the standard end can with your set up?

Also if fitting the 125 jets, will it run lean at all? especially futher abroad where the petrol isnt as good as here

thanks
 

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I have done all the mods mentioned by PUSD - PAIR removed, cat chopped off, 125 main jets and a K&N - and have had pretty much the same results. I also recently changed the silencer after rust got to the original, now running a GPR end can end & link pipe. It is only when I run the silencer with the removable baffle out that I get an inkling that it might be getting lean - popping and banging on overun, although that could be leakage at the link pipe/header joint as I didn't change the seal.

I have also taken the bike to morocco, although with the standard silencer at the time, and it ran fine although fuel consumption seemed worse which I put down to the heat, altitude and luggage not the fuel as it is the same fuel as in UK & france - there are Shell petrol stations and other french chains.

One other thing I think it was Recycler of this forum who has posted another exhaust mod - there seems to be a manifold constriction that would reduce exhaust flow. Recycler removed this and reported small improvements. And there was a report from South Africa (Louis Horn?) about some extensive (& expensive) exhaust mods and carb tuning but resulted in something 60bhp on a dyno - a 20+% improvement on standard.

Good luck with what you do - do it it to improve looks/sound, lose weight or improve MPG and you won't be disappointed; but do it to get significant power improvement and you will be.
 

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:thumbright:

Do you still run the standard end can with your set up?

Also if fitting the 125 jets, will it run lean at all? especially futher abroad where the petrol isnt as good as here

thanks
YES and no!
Mine was dyno'd with the stock can, now has the stock can but the baffle tube in the silencer 'kind of' fell out :thumbleft:, making it effectively a straight through system both my bikes are now like this and still run fine.

As Austin say's, running the bike abroad like this should pose no problems, we travelled two up through Bosnia/Montenegro/Albania/Macedonia and the bike ran fine although I'm not sure if their fuel is any lower quality EU spec fuel.

Austin, yes, I remember the topic of a restrictive weld in the top of the headers - was it Activemoto or BT bloke?
Aftermarket headers may not have this weld.

Phil
 

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Pleb
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One other thing I think it was Recycler of this forum who has posted another exhaust mod - .........
Wasn't me Austin, all I've done is fit a Staintune can on original headers.
Can't think who that was......

As PC Plod in Noddy says -
"What we have here is................a mystery.":eek:ccasion8:
 
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