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Converting pegaso engine to 36 mm carbs

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Got the last spacer made, this is how they sit on the head so ready for tomorrow. The inner one needs blending a little to match the port completely, but no worse than the original carb rubbers so happy with them for now. Might give them a little work at a later date, because it'll bother me other wise!

2013-02-28211218_zpsa22e133b.jpg

2013-02-28211225_zpsca39045c.jpg

post results tomorrow!

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I don't have any problem seeing them? Are you logged in?

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I don't have any problem seeing them? Are you logged in?

Nor do I. They're posted at Photobucket. That's considered a "social networking" site by some Internet content filters, so it could be that your filter is blocking it if you're at work someplace. Otherwise, it's an issue with your web browser.

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Spent 2 hours at PDQ this morning setting up the new carbs and trying spacers, and I'm a little dissappointed with the results:

dyno36mmcarbs017_zps632edd8b.jpg

Net result is 1 hp more, and an engine that holds on to peak power longer, with no losses anywhere, and a snappier throttle response. Peak is now a fag paper under 49 hp.

The red trace shows what happened with 20 mm spacers, a very minor boost in the midrange, not worth the issues it gives me with relocating the wiring to run the bike like that in my opinion...

Never mind, You have to try these things to see what happens!

Am running the bike with standard intake length which is the green trace, and I added the blue trace which is the original 33 carbs with standard length for comparison.

Still havent reached the magic 50 hp, which is a shame, but spring is here and hopefully the weather will pick up soon, so thats it for now until winter (unless I blow it up)

quick vid, filmed it the wrong way so oops.

Will do you a fly-by engler when I find a volunteer to stand there while I ride at them. Saw 114 mph with more to come on way home, which was nice...

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Hmm, now I think something else is holding you back.

What is the cam specs?

Valve sizes?

Compression ratio?

Also what do you use for an airbox?

Have you played with the ignition timing?

Even though you only got 1hp it runs much better than when you started.

. Do you have any way of knowing if the Vaccum slides opened all the way seeing how they are demand controlled?

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I think you're right there!

No airbox, just a foam filter covering both carbs.

I know the cam timing is conservative, timing figures are IN open 5 BTDC close 40 ABDC (225 deg) EX open 47 BBDC close 47 ATDC(234 deg)

Valves are fairly small, Inlets are 3 x 30 mm and exhaust are 2 x 32mm

Compression is low, 9:1

Not fiddled with ignition timing, I'd need a programmable CDI for that but on the to do list, especially if I change the compression ratio..

Not sure if the slides are opening all the way! the air filter was on for all the power runs, but I did swap the slide and spring from the old carbs, so assumed they would open all the way... not sure about that now!

If I'm honest I'm happy enough for now. I think more power now = major engine surgery, which means taking the engine out which in my case is an epic adventure! I'll do something with it over winter I guess

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I think you're right there!

No airbox, just a foam filter covering both carbs.

I know the cam timing is conservative, timing figures are IN open 5 BTDC close 40 ABDC (225 deg) EX open 47 BBDC close 47 ATDC(234 deg)

Valves are fairly small, Inlets are 3 x 30 mm and exhaust are 2 x 32mm

Compression is low, 9:1

Not fiddled with ignition timing, I'd need a programmable CDI for that but on the to do list, especially if I change the compression ratio..

Not sure if the slides are opening all the way! the air filter was on for all the power runs, but I did swap the slide and spring from the old carbs, so assumed they would open all the way... not sure about that now!

If I'm honest I'm happy enough for now. I think more power now = major engine surgery, which means taking the engine out which in my case is an epic adventure! I'll do something with it over winter I guess

Well, I doubt that your scooter is slow :) what's it weigh anyways about 5kilos?

But from what I can tell your a "well enough isn't good enough" kinda guy.

For some reason your project gets me all excited.

30mm intake and 32mm exhaust?

Is that right?

If it is &%$#@!?

My bore guestimater says you should have room for untamed larger. Something 34-36mm might be better. And also help make power with the little cam. But that's some work.

Can the ignition pickup be moved around or is it fixed?

If it had to have more power,

I'd check the squish and reduce it to like .030 (which will screw up your cam timing)

I'd increace intake valve size.

Play with the ignition to make it happy.

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30 mm intake is right, but remember I've got 3 intake valves so the valve area is about the same as 2 36mm valves?

ignition pick up is fixed, but I can probably find a way to move it a few degrees each way... ;)

I think the next step is to bump up the compression to 10 - 10.5 , but I'd have to deck the block to do that. The squish at the moment is so large as to be useless ( 2.3mm), but decking the block would close that up to around 1.4 mm (thickness of the gasket). Then I'd have to slot the cams to let me time them in again, make sure I had enough clearance from valves to piston (its tight!) and maybe get the piston pockets machined a little deeper. I have a spare mule engine in pieces, so I'll put that together and get the modeling clay out I think.

Performance isn't too bad, but I'm used to a 636 Ninja so its all comparative! I've got the weight down to 149 kgs without fuel, so without making carbon fibre fairings I think thats it I think. Allthough I did buy all the gear I need to do that so maybe if I get bored enough...!

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