Modern Vespa

The rubber spacer at the top of the shock?

I ended up using the Egig adapter which shifts the shock backwards. But if I'm not mistaken, it's a stock shock length with a rubber mount at the top. Yeah I think when you're hitting top tier stuff, your wallet will be emptying pretty fast… kinda envious of the Q kit.

You need to go all out and get quattrini cases…

But I'm betting it's also the fastest scooter you have in your fleet.

No, a shock spacer that sits between the shock and the rubber mounting buffer. They come in numerous lengths to match up pretty much any shock and ride height. It was an aggressive choice, and not really what I started out attempting, but since all the cheap alternatives were on backorder, I just went for it.

And at this point, my cases are fine. They don't do anything but hold the crank and gearbox, after all. It is definitely that! I thought the GL was fast at 27 HP, but this is a whole 'nother level.

Hmmm, know why you mean, I wonder if I need a taller spacer? You ended up installing the newer SIP shock? Famous last words… Yeah $ per level of crazy makes it a bargain.

Just found out there is no spacer on my rear shock…

Any ideas on normal length? 30mm?

With the SIP Performance rear shock, I needed about a 10mm spacer to get it back up into range. Not much, but it's no longer low-riding.

Ah got you.

Does it come with a longer spacer?

Is it this one?

Yes to the shock, no to the spacer. I just happened to have some in my Dragon Hoard.

Urgh… another upgrade…

Never ending.

Then there's the seat, which I'm thinking of a mono style seat.

And then the disc brakes… which I'm trying to figure out which is the best option… Quarta??? Or Crimaz?? Or PK fork?? Lol

And I haven't even ridden it yet!!

I'm rolling with the freebie seat on mine and it's perfect . Now, I just need to weld a nut to the frame for the rear seat post like FinYoshi does. I won't be swapping the fork, but I'm definitely starting to think hard about a front disc before I kill myself on this thing. That's your first problem!

Smallframes shouldn't need a spacer (at least that's what it shows in the parts diagrams). Both smallies I did were fine with just the top mount and a spring washer. Shocks were 340mm (Carbone Sport) and 345mm (Carbone HiTech)...

Awesome, that's perfect to know.

Thanks for that.

Reassuring to know someone's using the carbone hitech shock, was considering it

The freebie seat shape is pretty good if I remember. The 2 up seat is a bit boring…

You'll be on a disc before me it seems

The start is coming!! This week for sure!!

Need some wiring advice…

Managed to get it started again… (will post about it later)

But the electrics have died… no lights on start up…

Started trouble shooting. Thought it might have been the lights getting grounded. So found out the green wire was grounding and would break connection when you pressed the horn.

Took the handlebar switch out.

the grey and white wire (that goes to the horn) is also grounded too (touching the terminals there's a connection to ground)… how's that work???

There should be anything on that switch grounding right?

Also I'm not sure if I'm going mad, but the vape has an output of about 4v ac coming out of the blue wire… surely can't be right? I checked the stator… visually, couldn't see any problems with it. Blue to black connection has continuity…

Scoot starts with no problems though…

Sounds like you have the OG Balanced AC system. It takes a little bit of doing and some extra wires to convert over to a regulated setup. Or a new harness.

The horn, like the brake light, is a short-to-ground circuit. It's closed (shorted) by default, and when you open the switch, the path to ground is now through the light/horn, activating it. Disconnect the horn and remove the brake light bulb to start. You can also just not hook them up to the new system for now.

As to the Vape...

The AC out from the Vape should go directly to the regulator, nothing in between. Brown wire needs to be grounded to the bike, along with the base plate of the regulator, either bolted on or a ground wire attached to the spade connector. On older Vape's, the bike wouldn't run right if that brown wire wasn't grounded.

Check the output from the regulator, but if it's only 3-4V going in, I doubt it's going to be better coming out.

Are you working with a wiring diagram? If not, grab one. It'll be simple enough it should help clarify things. (as opposed to later or modern bikes)

Ah dammit… I attached 2 photos, looks like they didn't upload properly…

It's weird… it was working before… then suddenly died…

Oh, forgot to mention. I linked a wire from the regulated power to the brake light switch, with Earth disconnected. so pressing the footbrake lit up the rear brake light… that was working

That's the same handlebar switch as my Smallstate, I think. I disconnected the horn wire and the kill switch wire was blue(?), but definitely not green, so if that's wired into the AC side, that'd drag your voltage right down.

Brown/Purple on the lights are hi- and lo-beam out to the bulb. Red is power in. The two greens are one in from the junction box, one down to the horn. If you look at the back of the switch, you'll see the horn button is a normally-closed. you can cut that connection back to ground if you want to re-use the switch.

The three position switch is just on-off for the headlight.

You can re-use that switch, it just takes a couple cuts of the ground bus on the back of it.

Try connecting up the headlight next. That's the bulk of the load and will be a real test of the stator.

So that's the thing, red is kill switch (which is fine, doesn't matter the colour)
And it goes to the handlebar and has the Earth contact.

But I couldn't find a power wire, which I was assuming was green because there doesn't seem to be any other wires…

And from the wiring diagram there doesn't seem to be an obvious power too. So again, assuming it was the green wire

You can steal the green horn wire to get power up to the headset, then run another wire down to the horn. I think that's what I did, and right now the horn isn't even on the bike. I'm not 100% certain about that, though.

Unfortunately, I didn't take any pictures while I was working, so I'll have to roll back out to the workshop and just review my as-built to say for sure.

Looks like I'll be rewiring again…

Weird thing is, it was working before…

Didn't want to hijack John's thread.

But sorry Ray, just got your crankshaft stand.

Fantastic build… such a good design with the bolts!! It can accommodate all the cranks I need to measure.

Top stuff!

Thanks a million.

Been a while since updating on this build.

Have a little video uploaded. But not that exciting.

However I ended up swapping the phbh30 for a VHSH.

Atomiser needs swapping as it's a little lean and I couldn't get it to idle properly, it's rideable, but not quite there.

BUT! Some info on the jetting for anyone dialling in the main jet.

So I'm using a 168 main. I thought going down to a 165 would help out and I could richen up the air mix screw.

But lo and behold, it would stall after about 500m. Thinking that's weird, kept riding. Nope, still no decent idle.

Took the spark plug out and it was soaked. Thought it was a stuck choke, or stuck float… but nope, normal.

Put the 168 back in. Took it for a ride… came back… spark plug was ok, definitely not soaked, but wiped it dry anyway.

Put the 165 back in.

Did this 3 TIMES to double check, rode the same road. Similar throttle positions in the riding. No crazy deviations.

But each time the 165 made the spark plug soaking wet and 1/4 throttle sucked ass…

So just goes to show that you can't listen to just the numbers.

The jets are the correct size, ask me how I know (ended up buying a steel pin gauge kit!! See below)…

Measured half a dozen times to check. Can't be too anal about these things…

But wondering if it's anything to do with fluid dynamics? And the fuel getting sucked up the atomiser.

This…

The orange scoot, the frame drilled for the vape?

How's the speedo black box attached?

No, made a bracket that's held by the seat's bolts. 3M double sided tape for the power box…

VHSH is a great carb once set up. They are used for race engines and have many more adjustments than most. I have one on my 181.

What are all the numbers for components of your carb?

Yeah, it's nice and responsive. Can't beat a flatslide I think

60 idle
B44 idle mixer
Air screw 2.75 turns out
DQ 264 atomiser
K98 needle clip second from bottom
168 main

I trust the dyno test jetting provided by EGIG which would make it DQ 265 and 165 main… but I'll test it when they arrive.

Usually settings end up being more lean with me (don't know why. Just seems to be the case).

So far so good. All those parts are credible. What about float type, weight, height? Bushing size? Slide number? Pilot needle jet? Pump? Fuel filters?

This carb runs better on the road, when the airscrew is between 1.0 and 1.5 turns. Adjust the B44 to suit. Start at 0.25 turns, smoking and idle screw well in.

Copying jetting from another exact similar setup will get you close but when there's only 10% adjustment from perfect to damage, you still need to be cautious.

The VHSH on my 181 ended up on a 185 main jet but that doesn't mean much without the context of all other components.

Ah, will fill in the specifics:
300 float valve
60 Choke jet
12630 Float – 9.0 grams
7mm open tall bushing
50 slide
No fuel pump or fuel filter (the smallie tank is pretty direct to carb and the insides are clean I don't think it's the original tank)

What's a pilot needle jet though?

So, interesting with the float height, something I tried and learnt on the pwk because it has a clear float bowl (and with a lot of dismantling), is that I adjust the float so the fuel level submerges the hole the pilot jet goes in, but it's a few millimetres below the float bowl gasket.

You can see what's going on when revving it on the stand and seeing if the fuel replenishes properly.

It's not super scientific but hasn't failed since doing it on about a half a dozen Vespa carbs since then and on other bikes (hondas and BMWs). And ones I've compared to spec, it matches up.

With ones without a clear float bowl, it's filling the carb with fuel, emptying it and it leaves a residue where the fuel went up to. Takes a ton of patience because the carb can't move or it messes up the reading.

Of course jetting varies, but the people I end up asking, it's been a ballpark of about 10-15% of the jetting provided. In my case, I always end up on the lean side.

Stuck too many jets in now to know there's a difference between dyno jetting and real world jetting.

All the parts you've been advised are all good. The float needle jet is the same as float valve. The jet is more just jet, valve is the whole thing. I would have fitted a 350 for gravity but no issue.

We're talking the same with advice. 10 to 15% difference copied from another bike is a similar tolerance as, perfect jetting to damage. Advice helps but a 2 stroke has to be individually jetted. Everything ever learned from 4 strokes doesn't apply.

For the float level on a 9g is 13mm measure this on both sides and it's done. Clear bowl helps but not essential. If set to 13mm and doesn't overflow at max rpm, it's all good. Do this before jetting and never adjust again. Mess with the float and it all needs rejetting again.
Get the float and pilot set and I can talk you through the rest if you want.

Managed to install the DQ 265.

Goes like the clappers now... Pulls like a freight train in 1st, 2nd and 3rd.

Front wheel in the air 1st and 2nd.

Need to do more test runs, so I don't end up with one of those Chandler awards...

But feels pretty good.

He's another fella with a Egig 170 and PHBH 30

Newb question…

Swapping out new brake pads.

Which way to loosen the front hub main nut?

Something tells me it's reversed threads

Yes, reverse thread…

Thanks Safis!

Needed to triple check!

Any ideas on torque specs on that nut? I found 50kg/m.

But not sure about that number

If you torque it to 50 kg/m, you're going to twist that scoot clean in two!

The spec I have is 66-81 ft-lb's, which is 9-11 kg/m

Sorry my bad… I meant 5-5.5kg/m

I'm a newton meter guy so usually thinking in double digits… even thinking in ftlbs is better than kg/m…

I think that's what it says for the Vespa 50r in the manual

Question,

How do you torque reverse threads?

Torque wrench doesn't seem to click when it's set anti clockwise to tighten.

So how to make sure it's the right tightness on the nut?

Never used a torque wrench that didn't read in both directions.
Think that might be a tool issue...
Perhaps buy a cheap pointer (beam) type? - they are apparently quite accurate.

Yeah, even used my small torque wrench at 5nm, reversed still didn't click. So was wondering if they only worked one way.

Using basic Japanese wrenches, haven't failed me yet. But not had any experience with reversed threads.

After a small saga with the front hub (now I know the differences between the old 4 nut, 50 special and Pk type… lol), I managed to replace the brake shoes, brake hub and front shaft (who on earth designed a shaft which can't be pulled out?? I'm not a fan of hammering something hanging on the front fork).

Decent braking power which will have to do as a disc brake setup will have to wait.

But whilst shopping for disc brake alternatives, I came across Quarta in Italy… the guy makes mechanical disc brakes which is interesting. Minimal adaptation, looks pretty good, but I'll have to give up the 4 nut hub. Kit unfortunately costs a small fortune.

Then I came across Dexter racing who produce a 4 pot caliper for a 4 nut hub. Looks good too, not a super fan of the anti dive though… looks a bit too Vespa super for me…