Vespa Tuning Project.....

[Darrell Taylor]

Hi Dan will the bullet pipe u have fit a parma 177 ,be very interested in trying it on one ive tuned

[drunkmunkey6969]

Hi Dan will the bullet pipe u have fit a parma 177 ,be very interested in trying it on one ive tuned

Not as far as im aware, the 125/150 fitment on Vespa exhausts is different to 200.

[Jack221]

According to speedo which is out in 3rd it pulls about 65 think its more like 60. It goes of clock but gps it said it was doing 80. This i was unsure of so used a diff gps and it said nearly 75. So not to sure. Both gps readings were taken with head down on flat. I had ir dynod a while ag but was using standard carb then and on dyno went to 91 mph

Sounds like yours is going really well. With your bold gearing choice 60mph in third, is near enough the same revs as 80mph in 4th. When gearing for the track the revs should max out in top at the fastest point but on the road the gearing should be just too high to max out. IMHO if you are doing near 80mph on a GPS you have the gearing spot on for your power/lard ratio.

For the final tweek I want to get mine to do 8800 rpm in 3rd. Thanks to here, I think I have a cunning plan of how to get a few more rpm without messing it up

[philhnottm]

Hi Dan will the bullet pipe u have fit a parma 177 ,be very interested in trying it on one ive tuned

very interested in this as have a very steady 210 that needs some umph! 18BHP on dyno but struggles to hit GPS 70 unless its down hill with wind.

Just running in a Parma 177 build so even more interested as to what Darrell can do to these a sit feels far quicker than either of my 210's already . It didn't last long last time so need to make sure its right second time around.

[Darrell Taylor]

Hi Dan will the bullet pipe u have fit a parma 177 ,be very interested in trying it on one ive tuned

very interested in this as have a very steady 210 that needs some umph! 18BHP on dyno but struggles to hit GPS 70 unless its down hill with wind.

Just running in a Parma 177 build so even more interested as to what Darrell can do to these a sit feels far quicker than either of my 210's already . It didn't last long last time so need to make sure its right second time around.

the parma 177 did 17bhp on 30mm carb and malossi reed kit and jl pipe when id set it up
what might be of interest is it nearly blew up too on its way to me for dyno,i found it needed unusually large pilot and main jets so suspected something wrong and found an air leak from the malossi reed housing,stripped down and turned out the housing overlapped the case gasket face by quite a lot so wouldnt seat down leaving a full gap of approx 0.5mm,i guess this will be a problem on most builds as only way to cure it was to port the housing to remove a few mm of material before it would seat down

should be back for dyno nxt week to see what the tune has done

[drunkmunkey6969]

good results from a 210 look forward to the flat out road test to see what speed it pulls as that rpm extension will work really well on it.

Thanks, yes pleased with the result, especially with standard head, ign and 30mm carb etc. Will let you know how the GPS run goes.

Right, sorry for the delay, been busy setting myself on fire and such like. Anyway, before I went up in flames, I did manage to get out on the scooter, and did a GPS run on it.....84mph in 4th gear. So does what it says on the tin.

However, cant say I like riding it.....the 21bhp with revolver exhaust and lower port timings was to slow for me, hence embarking on this experiment. I got what I planned for, but cant say I like it now I have it......

And why don't I like it? Anything above 1/4 throttle in 1st and 2nd gear lifts the front end, which is fun at first, but quickly become a pain. 3rd gear is great.....very wide power band, pulls like a motherfucker, if all gears worked this well then id be happy. 4th, well it does pull 4th, but i'm wringing its neck in 3rd to get it to drop into the power in 4th. If I don't do that, 4th doesn't pull well, its more of an overdrive at that point, so has to be thrashed in 3rd if you want to keep the speed accelerating in 4th.

I figure with headwinds, hills and luggage, this will become a nuisance. I could re-gear to make 4th more useable, but 1st & 2nd would become even more brutal then. This setup is perfect for sprint meets, racing, and hooligans......but i'm actually a bit worried that I may be getting old, as I think I may prefer something a bit more 'broad' rather than 'focused'.

So.....the plan now is to make a short sleeve, which will fit between the slip joint on the pipe, and thus artificially extend the tuned length of the pipe......which is a cheap/easy way of experimenting with different peak bhp/rpm/tq ranges, and bringing peak power down the rev range, in order to increase torque. Its not the BEST way to do this, but it is quick, easy and leaves me with the option to pop the slip joint in/out as and when I want to do different things with the scooter.

I think that if I can tweak the power delivery with the use of the slip joint (and a couple of other adjustments) so that I drop maybe 2bhp, peak at around 7500rpm, gain 2ft-lbs torque, and bring it on pipe a tad earlier too, then it'll be more useable on a day-2-day basis......but still with the option to remove the slip joint as/when/if i want to scream around etc.....?

Might work, might not....enjoying the project though!

[goldeneye]

sounds like quite a powerful malossi Dan, but if you cant get in the swing of it..... put a PX125 gearbox in, and have 3 gearing options with a 20/21/22 tooth clutch cog...10 minute swap. lammy lads swap gearing to suit pipes, but vespa lads chug along all day out of the power...... most malossi 210"s , even with the T5 4th, struggle in top gear. change ya gearbox and itll fly on the ROAD.

[Spanish Fly]

Dan.
Good thread, this.
Get well soon.

Assuming it has a packer to accommodate the longer stroke. Where is it? Head or Barrel? Is there scope for juggling?

SF

[LI150]

sounds like quite a powerful malossi Dan, but if you cant get in the swing of it..... put a PX125 gearbox in, and have 3 gearing options with a 20/21/22 tooth clutch cog...10 minute swap. lammy lads swap gearing to suit pipes, but vespa lads chug along all day out of the power...... most malossi 210"s , even with the T5 4th, struggle in top gear. change ya gearbox and itll fly on the ROAD.

agree about gearing best thing for 210's

[drunkmunkey6969]

OK, so.....latest update on the Vespa project. I'm happy with it now, seem to have it where i want it. Got the SIP tubless rims n tyres on it, uprated the shocks to BGM, and fitted the 'HotRod' scooters swing arm bushes to firm it all up, feels good on the road now in terms of handling and stability.

Engine, i've done a whole heap of changes in one go, so again...no definitive/incremental figures for each change, but the 'overall ride' is how i want it now, so am happy. Basically engine spec is: Malossi 210 kit, very mild porting work to piston and cylinder, 60mm 'bell shaped' reed valve crank, V-force 4 reeds, 30mm flatslide carb, and pipe-design exhaust.

Since my last round of test rides and dyno runs, i have played around with port timings and packer plates, to drop the exhaust duration a fraction to try and get the torque up a bit. Along with the those changes I've also played with ign timing, fitted a new head with lower comp ratio, set squish up a bit better, and also removed the internal stinger from the exhaust as it was creating too much heat.

The upshot of all these changes is -1.5bhp at peak & +2bhp & 2ft-lbs torque mid-range. So now the scooter drops into 4th gear much better from 3rd and pulls very strong and very clean. Conversely the 1bhp drop at the top end is not even noticeable on the road, and the GPS speeds are still in the low 80's. I'm also getting used to riding 'off-pipe' in 1st and 2nd so that i don't wheelie it everywhere! lol

Here's the new graph to show the changes to the curve, which allows 4th to pull better:

BHP: old in blue, new in red. Good power gains upto around 7500 rpm, with minimal loss after.

bhp by drunkmunkey6969, on Flickr

Torque: old in blue, new in red. Torque up for the best part of the rev range.

Image by drunkmunkey6969, on Flickr