Modern Vespa

Was that 4% forever? Or just the break in period?

I'm imagining it's more to do with lubricating the bearings and cylinder walls because of the extra stress they'll endure. Usually it's 3% though for other kits. But I haven't seen any info on how the extra oil helps tbh.

Forever is my take from the instructions... here's a translation fyi. Not sure what ratios particular makes of modern bike use, but after a bit of a search it looks like anywhere between 4% (25:1) and 2% (50:1) is normal, with smaller capacities tending to use a lower percentage of oil. One thing said that more oil helped seal the rings better.

I'd trust the instructions.

Google translate at its best.

You don't hear many quatrinnis having problems.

If the oil is 4% it's up the main jet 1-2 points.

The 4% will be for running it on an SI24/24. There is no combination of jets where a 24 will supply enough fuel while running factory smooth and not wear out prematurely.

You'll ok on 2% with your carb once run in cycles are done.

Once 3/4 is good enough adjust the pilot jet to get 2.5 turns at about 1500rpm.

I was in a hurry to order the atomiser before work the other day and scanning through the list I ended up accidentally ordering an AR instead of an AS. Duh.

So trying the on the stand no main jet thing today, it still started to flood at 1/2 throttle give or take. Of course had no leaner atomiser to put in. An AV 264 should arrive tomorrow and an AS 264 is on back order now.

So is this test to choose the atomiser?

Can't remember if it's a Reed or rotary setup…

It's the Malossi reed.

Then I'm not sure you'll use the AS264.

I was using an AS264 on a rotary setup with the malossi 210.

I think your quatrinni will have larger fuel demands.

I'm guessing you'll eventually end up on a AS266 or 268 with x2 needle.

Interested in how you get on.

But you are using a Polini box. But x13 will be a little lean.

The AR264 isn't the worst mistake. Just a bit richer than the AS.
The 3/4 test is actually for the taper. As the X13 needle is already the biggest tip and shorter length, there's nowhere else to go but smaller atomiser.
Once flooding at 3/4 it may need a different needle. Assume you have the whole 1.8mm usual suspects handy.

Unfortunately the AR is different shape and thread again, so unusable. I'm annoyed that I didn't think to order from ze Germans when I was spending heaps! I might ask around locally to see if anyone has a spare.

I have a set of needles -2, 3, 4, 6, 7, 13, 25, 32, 44 and 61.
No X12.

AR is should be longer. Fits carbs that go on BMWs airheads.

x2, x7, x13, x25, x4 are the go to's, I think you're covered.

Oh I have a spare AS266 I can send your way. But unfortunately no AS268. Never had the need for it on a 210.

Yes it's quite long.

Thanks very much for the offer, appreciate that 108! I should have an AS266 and an AV264 waiting for me at home in the letterbox (unless I buggered it up again! ).
From your earlier comments they might just do me, it'll be interesting to see the difference the same size in AS and AV make. You think the AS runs leaner?

I guess if it's still flooding before 3/4, I go to a leaner needle?

Ah great, let me know if it's worth your cause sending it over, saves waiting an eternity for small parts. Yeah, when I first got the phbh, it came with a AS264, not knowing what I was doing and reading what most folks in the UK run a AV264, I basically brought a AV262, 264, 266 and tested those. I ran with the AV264 for a good few months, thinking it's the one.

Then I threw a spanner in the works and started asking around and testing the AS262 thinking I needed something leaner. Brought an AS266 to cover anll bases. And landed back at the original one… the AS264. You remember that vividly when you're thinking to yourself "dammit, I didn't need to buy all these jets in the end…"

But it was a lesson learnt though.

AS vs AV runs a tiny bit leaner at idle, but more importantly the fuel flow is less between certain points as you open up the throttle.

A crude example would be running the engine, opening to 1/2 throttle, then cutting the engine. Pull the spark plug and the AV will be more wet with fuel than the AS (granted the main jet isn't humongous).

I honestly don't think I'll even end up using the AV atomisers for a Vespa engine ever now.

Thanks a heap, but I'm sure there's someone at least 10,000 miles closer in this direction that has one in a drawer somewhere. Really do appreciate it though.

Ok I think I'm a bit better informed on the atomiser situation. I'll see how I get on this weekend, hopefully the ones that arrive today will let me move on to the next phase.

What is your PHBH on? Is that the 210 you mentioned?

That's a decent needle collection. The 61 is favorite atm. AS264 is the one you need to try to get the 3/4 closer. The AV264 should show some improvement but unlikely to be enough.

My PHBH started life on a rotary 210 sport 221cc, then got upgraded to a worb5 cylinder, still used the PHBH. Then it got neglected until I installed vforce4 reeds on. Installed the PHBH in-between getting frustrated with a PWK air striker and a pwk 28.

Tried it for giggles but it worked pretty much straight away, however I'm a sucker for flat slides.

Then I threw the PHBH onto the egig 170 engine, was great, until I had the sinking "flat slide" feeling again… then it got replaced with the VHSH.

The PHBH is great, it's reliable and fairly easy to get the jetting working. And I have all the needles and jets for it. 75 mains all the way to 180. 47 pilots to 60. So I won't be needing to shop for anything any time soon. Oh and I brought a 30 and 50 slide… the 210 ran best with the 50 slide. Especially with the rotary valve.

Now, it's on the shelf waiting to become another backup.

Yes it's the BGM box, a fair bit cheaper to buy like that.

I tried the AV264 that arrived today and still half throttle flooding. Dropped the needle from second to first clip and it took it to 3/4. That might be cheating though.

I put the word out for an AS 264, I'm sure one will turn up shortly. Otherwise I'll take 108 up on his kind offer. Hmm. I need to talk to you about my Pinasco 144 and the VHSH I have sitting here... another time!

Why not use the VHSH on the quatrinni?

You should be working on the smallie!

That's good progress. One clip for all that change is a bit scary.
Put in the x61 for the next try. Keep the main jet out until the final stages.

Tried the AV 264 on 2nd clip still around the half throttle. Same for the X61 needle, not much difference in this test at least.
So I went to the X2 needle on 2nd clip which took it out to 3/4 ish.

I found someone who has an AS264, hopefully I'll get it next week sometime.

Actually I was wrong and its a VHST (28), not H. Don't really know the difference at this stage! I have limited experience with the PHBH, zero with the VHST. And only the jests that are in it...so I'll leave that one alone for now. Plus the smallframe is still not on the road!

VHST is a smaller flat slide, with a slightly different design, looks good. But umph… wouldn't want to play around with the VHST, there's 4-5 different styles of atomisers!

Hopefully there's someone with ballpark jetting to help out on that one. But imagine it's a project for a rainy day.

Well that doesn't sound like my idea of a good time! I'll keep an eye open for someone using one.

Well the AS264 arrived today, and along with the X13 needle on the 2nd clip (no main jet) it flooded out at petty much exactly 3/4. So that was a relief to get that happening. I guess now I choose a main jet?

Sounds too lean, but keep going…

I would only be using the X13 if the X61 is too rich at 1/4.

This is still just roughing out. Still no main jet.

Adjust the mixture screw/ pilot jet for 2.5 turns at high idle speed. If this is wrong, everything else will be wrong.

Next step is to set the clip to check the needle is staying. Set the clip at just over 1/4 throttle. Not more. Set really rich. Won't rev loads of smoke. Then reduce until revving well.

By "set the clip", you mean try different needle clip positions?

And should I be trying this still on the stand or on the street?

For the clip adjustment it's more accurate to ride it. Try the X61 first. The 3/4 point will be slightly later but close enough.

How did the pilot jet work out?

On the stand - haven't had a chance to ride it as yet - the X13 was quite clearly flooding out at 3/4. The 61 was more "muddy", if anything started flooding earlier.

What size pilots do you think I'm going to need? Just realised I only have the 55... but can order some more that could be here early next week .

The X61 is richer low down, requiring the mixture to be adjusted between needles. This will exaggerate the muddy area. I worry the X13 will be too lean under 1/4.
If you can't get the clip adjusted when riding, go with the X13. Unless you have an X32.

Just to be clear - when you say adjusting the clip, you're talking about raising or lowering the needle, right?

Also, while making those adjustments, the mixture screw should be left at 2.5 turns out?

I do have an X32 in the set.

Great, use the X32 until you have reason not too.

Whenever changing needles, adjust the mixture screw again. Set a high idle, start rich, adjust until it speeds up. With the correct pilot jet this is 2.5 turns.

Setting the clip is moving the needle richer or leaner. The clip position nearest the blunt end is clip 1, the weakest. Start at the richest clip. Check 5/16 throttle rides like crap and a cloud of blue smoke is following you. Lean the clip until it rides nice at low throttle and will hold a steady cruise while maintaining low cht.

Recheck the 3/4 point and migt be ready for a main jet.

Cheers Jack. As mentioned, I only have one option (55) currently for a pilot jet so that bit is going to have to wait. I've ordered a 46, 50, 52, 58 and 62.

So X32 rode ok, 4th clip horrible, 3rd clip somewhat rideable, 2nd clip good but flooded out about 1/2 or slightly wider throttle. 1st clip more clearly flooded out at 3/4.

All positions meant the mixture screw was between half (at 3rd clip) and one and a half turns out (at 1st clip).
I suppose that means I need a smaller pilot?

Rode quite smoothly at 1/4 throttle, bit lumpy around 1/8 unless accelerating. CHT was steady at 230-240F at 1/8 and 240F-250F at 1/4. That was on 1st clip.

Acceleration was nice when I tried a few quick bursts up to the limit of the no main jet.

Can't really ride without a main jet at anything much over 1/2, as it gets spluttery.

AS264 X32 clip2 all sounds good. 50 pilot will probably get you near.

You have all the main jets up to 200? I expect you do.

I spent the family fortune on needles. My main jet set is only up to 150 - didn't expect to go much higher than that to be honest. I can only buy individually as the sets stop at 150. Any suggestions?

Surprised. All the modern kits are so much more powerful. Main jets just keep getting bigger.
This company ships worldwide, you'll need two box sets to get up to 200.
https://www.kmtproducts.co.uk/?cat=DELLORTO-TYPE-JETS&subcat=M6075---6mm--Dellorto-Type-6413-&page_id=62&menu_id=75&category_id=1&sub_category_id=10
I'd hope you're 244 ends up about 180. We'll see.

That is a good price for a set of 10 jets! And I've bought their stuff in the past. Unfortunately you actually have to commit to buy before they tell you how much shipping is... stuff I have ordered from the UK has taken around 10 days to 2 weeks to arrive here. I do appreciate the suggestion though.

I'll pay just under double that per unit from my local supplier and they'll be here on Tuesday with free delivery. So I'm thinking I'll get 6 in increments of 5 points up to 180, once I get it close I can narrow down to a 2 or 8.

I have a 500 mile ride coming up at the end of the month so not keen on waiting for bits to arrive.

It's actually a 252. Think the timings ended up at 124/180.

252 that's big. The timing as a 244 must be pretty conservative. With the 62mm crank it remains on the low side.
Still, with a box pipe and this 30mm drum carb, it's going to be solid. Definitely going to do 75mph. Cruise at 70 most likely.

You're going to need to start the main jet at 195 to be sure you've not made a mistake at 3/4. Need more jets.

I got some useful info from this series of articles. He's used a Kingwelle 62 but it has a 128mm rod instead of the 127 that's on mine. Some interesting comparisons are made, he never actually gets to the alternative carbs though and sticks with a 30 although it's not entirely clear which one. Anyway the changes to port timings and the relevant dyno charts tell a story.

https://en.blog.scooter-center.com/alex-baut-einen-quattrini-252ccm-vespa-motor-quattrini-m244/
https://en.blog.scooter-center.com/alex-builds-a-quattrini-252ccm-vespa-motor-2-quattrini-m244-king-shaft-of-the-super-tourer/
https://en.blog.scooter-center.com/alex-builds-a-quattrini-252ccm-vespa-engine-3-expansion-stage-2-with-exhaust-test/
https://en.blog.scooter-center.com/alex-baut-einen-quattrini-252ccm-vespa-motor-4-ausbaustufe-2-mit-auspufftest/
https://en.blog.scooter-center.com/alex-baut-einen-quattrini-252ccm-vespa-motor-5/

Unfortunately the display of some of the pages has gone all out of whack in the the last couple of months for some reason, but the info is still there. Aye aye Cap'n. Will add to the order.

Always surprises me how guys build a tractor engine, then do everything they can, spending weeks on end, trying to make it go faster. Why not just build a fast engine. An MHR with the same effort and budget would be 10bhp more.