Modern Vespa

Hey guys, my installer is having an issue installing the SIP Digital Speedo on my VBB, and was hoping someone might know the answer:

He is looking specifically for a breakdown of the speedo sensor wires. Can someone please let me know which color wires on the speedo sensor are what as this is not listed in the instructions.

Thank you!!

Hi Mark. Serious reply here. If your answer is "I know" then great, we can rule that out.

The digital unit takes its speedo sense from the same speedo wire you had installed before you bought the SIP gauge. What looks like the speedo needle on the face of the speedo measures RPM rather than speed. Your speed will be displayed as digital units below this.

My answer is that I don't think there is a speedo sensor wire which is why you can't find one in the freeky deeky German translationy manual. I wired mine from the manual ok.

Thanks Scott. I'll pass that along. Fingers crossed.

On a side note, how is your digital speedo treating you? Any bugs or irritants to pass along?

I apparently misspoke about which wires we needed clarification on. Below is a better text from the installer that might make more sense:

Wires: Yellow with black, orange, and yellow with white. This are coming out of the speedo . Not the sensor I have sensor diagram. Right now there a ground. And two power leads of 4.8 volts on a 12 volt system. I have searched the site but no one has a posting.

Here's the other wires they need to connect to.

The wiring instructions should be included in the box with the speedo. If you don't have it, PM me and I can send it to you.

There were instructions in the box, but these three wires were not detailed in it. If you look over your instructions and see they are listed on it, please let me know as they are not listed in mine.

Thank you!

Is your VBB 12 volts? I'm not sure the speedo unit will work on 6 volts.

The problems I've had with mine were the inner speedo cable not long enough to connect into the instrument enough to turn the inner mechanism, solved with a brass compression fitting for connecting a 1/4" water line and the RPM needle getting out of phase with the actual RPMs, either too high, or as it is now maxing out at 4500. I have almost 6000 miles on mine. I suggest getting a Koso 10mm cht fitting and use it under a head nut instead of using the spark plug. I used the headlight power wire to the handle bar switch for powering the speedo, and the other wires were plug and play (that was for a Rally unit, the VBB could be different)

Yes, 12v system.

From those pictures it looks to me like your guy has just cut off the plugs and forgot to check where they go? They're all unique and only fit one way.

There's one plug for the external button (two wires), one for the cht sensor (two wires, I think), and three wires coming out of the power box connecting to the rest of the scooters wiring (Red (+12vdc or ac power), Brown 12v ac (rpm signal) and black (ground).

Perhaps you should take a look at an other sip speedo and peel back the extra isolation to see where the wires go?

There are some extra wires for optional extras.

Go into your SIP order and you will find a PDF version of the instructions right there.

Mine has been working fine. I didn't have an R rated plug to start with so disconnected the CHT sensor at the plug as it was making the rev counter do its slow advance to the right until it goes no more. I've got R rated plugs now and it all works great.

When it comes to setting the RPM's, ignore the manual which I think tells you setting 1 for 1 cylinder, 2 strokes. Just keep it at default which i think is 3.

I've only got about 3000km's on mine but its a cool addition.

Your scoot survived the hit scott?

TBH, I've yet to see it properly in the flesh and assess as I only had my operation a few days ago. I think/hope it can be fixed with some welding to the legshield and a new floor. But the photo I saw was like an IED had ripped the lower leggy and floor apart.

We'll see. But it will take time. I may have to relegate it to a Sunday fun tool because with the mileage I do (about 1500km a month), I really need to a) increase my chance of survival from the idiots that we have to deal with here on the roads and b) a vehicle I don't care if it gets smashed up. Hence I'm buying an S125 3V! My thinking is I can't go too fast on it, brakes are very good and a slight bones is I'll get double the gas mileage compared to my Malossi monster. Jon was right when he built the engine. He said it would pass everything except gas stations!

I've had one in a P-series for about 1 year now. My only complaint is there seems to be quite a bit of dust/moisture under the glass now - especially for only being 1 year old. I garage the scooter 99% of the time (only rarely do I leave it parked on the sidewalk in front of the house over night.) Otherwise, I love it!

So the SIP rev counter/speedo is installed, but I'm having issues with it locking up a lot. The only way to fix it is to turn off/on the scooter to reset it. Also, its not reading RPMs. Has anyone else had this issue, or is this a cut and dry case of "exchange it" and try again?

install a resistor sparkplug and see if it's better.

Also, here is what I heard back from Koso via SIP about the wiring questions I was asking:

About the wiring definition : Please check the information below for your
reference.

1. Yellow/ White : Signal
2. Orange : +5V DC
3. Yellow/ Black : GND About installing a resistor sparkplug, are you thinking the speedo display is getting too much voltage? I'm curious to hear a little more about this.

The ignition on these are very electrically noisy and this can freak out some computers (bike speedometer, trip computer...). I've had trip computers lock up as soon as you start the bike, installing a resistor type spark plug was all it took to correct it. It's cheep and easy to try and has no down side.

May or may not be the cause, but worth a try.

Resistor plug is the way to go.

I can't remember if it's specified in the manual. Perhaps not, since so many people have this problem?

ok, popped open the spark plug to check and it is a resister plug. NGK BR8ES to be specific. Any other ideas before I pull out my hair???

also will the plug cause the input signal to have power on it when it is not hooked up? Because that's what I have going on.

let me re-clarify. Here are the words from the installer directly. Please chime in with any suggestions. At this point we are trying to rule out everything other than "just exchange it":

"On the three wires that are coming off of the speedo (not the sensor), there are power on two of the leads, where there should be only one and a returning signal from the sensor only. This is why i think the SIP speedo is having issues (outside of the other issues that I have see with it). This is happening with the key in the "on" position only. The unit is wired correctly based on the manual provided. Maybe this helps?"

That might be be the rpm signal (12v AC from the motor) he's talking about.

To be honest, I'm starting to doubt that your installer should be working on your bike for you.

I'm pretty sure you'd be able to do this pretty well yourself.

It really isn't difficult. The hard bit would be fishing wires through the frame.

It seems to me he has made a rather simple installation into something alot more complicated by cutting over all those plugs.

Show him this diagram and ask him which plugs he has cut off and where he is measuring what? +5v dc tells me he might be measuring something between the powerbox and the speedo. Between the powerbox and the rest of the loom he should be seeing 12dc and/or 12v ac.

Then again you might have a bad speedo. But that's a little hard to tell when I can't be certain it's wired correctly. The input signal (brown wire) will have power as long as the engine is turning. (for instance when you're kicking it over.) The plug doesn't need to be installed, and the brown wire doesn't need to be hooked up to the speedo. The signal is just the AC pulse from the stator.


Assuming it is wired correctly, try disconnecting the temp sensor, and make sure the brown wire is connected to 12v regulated ac. Does it still freeze up when the engine is running? What happens when the engine is off?

So I finally had a chance to see this for myself and the issue is basically that the display is very temperamental. The unit will randomly decide if it wants to go into Setup mode, or even allow the hardwired button to even function at all. Sometimes it works perfectly, sometimes it freezes up at startup, sometime it freezes up after I enter Setup Mode then cycles through all 5 screen after I was able to input all my settings. After boot up, I can press and hold the button for a minute or more and it still will not trigger the Setup screen. Then after a little time, the setup screen will just pop on without me pressing anything. I've also noticed that when I free spin the front tire, the RPMs will jump from 1, 2, 3, 4, to 100+.

At this point, I'm having to agree with the installer that all things aside, the speedo head unit software is acting buggy. I'm in talks with SIP right now for an exchange, but I'm finding they are not very easy to work with for exchanges. It's been a couple weeks now and they still have not approved the exchange yet.

I need to install a Koso speed sensor for this speedometer, but I am confused by which speed sensor I would need: Active or Passive?

The SIP website shows a picture of a passive sensor, but it has the active sensor model number next to it. With no description next to it, I am obviously very confused.

Can anyone shed some light on this? Here are the links in question:

SIP Website:
http://www.sip-scootershop.com/en/products/speed+sensor+koso+sa07+_kobf640j04

Koso Passive Sensor:
http://www.kosonorthamerica.com/koso/shop/sensors-scooter_access/passive-speed-sensor-8/

Koso Active Sensor:
http://www.kosonorthamerica.com/koso/shop/motorcycle_acc/active-speed-sensor-200cm-4/

EDIT: KOSO and SIP both say to use the Active Sensor. Exchanged Speedo Unit, Reinstalled identically, installed Koso Active Speedo Sensor, and everything but the RPMs were working perfectly. At this point, screw the RPMs, I'm just happy to have something digital working on technology this old!

I'm wanting to order the speed sensor. Did it come with everything you need?

It doesn't come with an active speed sensor, speed sensor bracket, nor magnetic bolt. Beyond that it had everything if I remember right.