Vespa Subframe Reinforcement

So this past weekend, I decided I'd reinforce my Vespa subframe on my grande... Earlier this year at THHHEEEEE BUZZARDS rally (which was epic, even in the back of the break down vehicle) I was 25mi into the 100mi ride on Saturday when my right tab broke off my subframe at about 45-47mph. Needless to say this was a harrowing experience and my moped riding for the weekend was over.

The Vespa stayed parked for a while, because I couldn't decide whether to replace or rebuild the subframe. I didn't have a welder, so rebuilding wasn't an option at the time. I had gone ahead and made templates for plates and began to cut them out with my angle and die grinder (very time consuming). I built up an OA rig and was contemplating doing the project with O/A - I'm so glad I didn't do this because the welding would've taken forever. Unfortunately, my cutting torch parts still didn't get here in time so I had to mechanically remove material any way. This past weekend I picked up a miller promig 135 with gas shielding (and a bunch of HID stuff ;) and I decided to go for it since it was my fall break.

I did some work on Thursday when I got home, but it was mostly getting all the kinks out, setting up the welder and riding with nashville's vintage motorcycle group Pseudomoto. The CB100 rode great and got me in shape to work on the Vespa.

My plan consisted of using cold roll steel to inlay the cutout of the subframe. I used 1/8" for the major inlays. It's been over a year since I'd had any time on a welder, so my welds weren't pretty but they should hold just fine... I didn't lay anything that was so bad I had to cut it out, but it definitely could have been better. I made sure to put a bevel on the pieces that would be adjoining to thinner material - this along with torch angle is important to get a consistent heat and penetration when welding together materials of different thicknesses.

Here's some footage from me working... not as epic as I wanted it to be... cam kept dying :/

In my infinite wisdom, I did not do a fit check with the transmission components installed with everything tacked toegether, and I ended up having to remove metal from my main reinforcing plates after welding them in completely. This made it way uglier and take way longer... IF YOU REINFORCE A SUBFRAME THIS WAY, DON'T FORGET THE TRANS CUT OUTS!!!!! This was a HUGE disaster and I would've finished the bike Saturday instead of Sunday (because the paint took a whole day to dry) as I didn't have it in me to finish fabrication Saturday night after this mistake.

From there I did some cosmetic welding and sanded everything down and started prepping for paint (and of course did another fit check before paint lol).  I decided to go with two coats of automotive primer and two coats of Rustoleum gloss enamel.

Re-assembly went fairly smooth except for the 4 bolts that go into the rear transmission housing were too short with the lock washers (I need to get new ones that are long enough for lock washers) and the main bolt up front that the subframe hinges on was too short. Everything else went smoothly and the bike was back together and running.

For Those Thinking About Doing This:

 

I would suggest including the trans cutouts in your design if you decide to go the plate overlay method.

Another thing I would suggest to those who would want to do this in the future is to consider using round stock instead of plate. The plate was incredibly thin in some spots and certainly could have been thicker. Round stock would allow you more flexibility and be way easier to manipulate.

Lastly, I suggest you just make another subframe entirely. After having done a reinforced subframe, I think that if I'd had an oxy-acetylene torch setup functioning or a plasma cutter, I wouldn've just gone this route. It would've been more effective and easier. I'm not sure I'd recommend doing it out of plate either - I really think that maybe next year I'll build a tube sub-frame. I'm not incredibly satisfied with the reinforced stock subframe.

Some how I picked up 5mph during the rebuild...

I took her for some speed runs and I guess she's loving the cold weather and not having a huge gaping crack in the exhaust :) I hit 52mph with stock vario notched with my aluminum weights, gates AX39 tri-power belt and a polini blue contra in the back with a 13mm carb and a DR65. The amount of vibration is still a bit disconcerting, so a mazi crank this winter (thanks for the suggestion Joe) and a homeade dynamic balancer for my stock vario (that'd be fun right??) or a polini vario are in order. I can probably build a ghetto balancing setup cheaper than I can buy a polini vario and weights, so I'm probably going to go that route... would be awesome to offer that as a service to all the stock class racers...

The subframe is fixed, but before next rally season ...

I set some parts on the bike to see how possible throwing a disk brake on the front would be and I think I'm going to go for it this winter since the forks are substantial enough, hyrdaulic and the fork lowers are steel. The setup would be a Z mag with china disk fitted and a honda caliper and master cylinder with a custom stainless line from the local hose manufacturer. With a disk brake, this would be the ultimate doubles bike for knoxville campus or rally bike period. I'm super stoked to bring this bike back up here next semester and rally on it next summer if/when I get out of school :P

Tri-Power Gates AX39 Belt for Vespa!

Hey guys,

So I found this awesome belt the other day while I was at Oreilly's. It's a tri-power series belt.

It says it's oil resistant and rated for temperatures over 100*F higher than what the standard belts are and is oil resistant.

It says it's also static conductive, so I feel like that means it's got a metallic element. Anywho, I'll be testing this out on my Vespa grande and I'll be sure to report back.

The standard gates AX39 that I had on there only lasted about 5 months of sparse riding.

Also, if you buy from oreilly's, they guarantee it for three years no questions asked! I told the guy I'd probably shred it on my vespa this summer and he said it didn't matter! Just bring it in and I'll get a new one! Gotta keep your receipt though.

Here's a link to a specs sheet on all the belt series offered by gates:
http://www.gates.com/ptpartners/file_display_common.cfm?thispath=Gates%2Fdocuments_module&file=Vol_57_No_6_High_Temperature_and_V-belts.pdf

Vespa Performance Variator weights for Stock Variators

Choose Variator:

Vespa (5 weights) $15.00 USD Camino (6 weights) $18.00 USD Vespa/Utah (8 weights) $22.00 USD

Weights can be purchased by clicking the add to cart button and proceeding with paypal checkout. Price includes shipping to your door via USPS parcel post. 5, 6 and 8 weight sets are available for vespa stock, camino 6 roller and utah variators.

These are 6061 aluminum roller weights that fit inside your stock vario plastic roller covers to replace the brass or steel weights you are currently running (that weight about 8 grams undrilled).

For those with questions about longevity - I have about 600mi on the set in my Vespa and the cages are perfect. The issue with using nuts, wire or anything that isn't 11mm in diameter, is that the plastic cage ends up pushing the vario cheeks together, instead of transmitting the force to the roller inside. The weight covers are only meant to slide easily - not bear load. This is why the nuts, wire etc. others have tried to use do not work or fail quickly.

6061 is about 1/4 the weight of the brass rollers. Each set weighs between 2.80 and 2.90 grams ea with no more than 5/100th's of a gram deviation between the sets you will receive.

These are 11x11mm. Drill/tap to add steel set screws/threaded rod for additional weight or just drill for less weight. These are a bit of a snug fit - they won't drop in, you have to use some force to push them in, but not much - it's a snug, but not high interference fit.

Vespa Wiring in a Nutshell

Had a guy ask me about vespa wiring, and I sent this as a response. Figured I'd post it so more people than just him can enjoy it. This is written for bikes with turn signals, but applies to pretty much all vespas.

An Overview

You should have four wires coming from your stator area if you have turn signals. Two should be white, one should be blue, and the other wire goes with the blue wire (don't remember color, could be any). Just the blue and violet if you don't have turn signals.

Power for lights and horn comes from the red plug in on the side of the case and the copper grounding strap. Red and black wires from your harness should plug in here respectively. This is 6VAC for lights and horn - but does NOT power your brake light, only your tail running light, headlight and horn.

The two white wires are a 6v coil with floated ground used to power a full wave rectifier and charge your lead acid battery which powers the turn signals - disregard these two if you don't care about turn signals.

The last two are the ones for the ignition. The blue/violet is for the HT coil. It has a split where it plugs into the wiring harness. One side goes directly to the HT coil, the other into the harness where the lead is grounded to the frame when you hit the kill switch dumping the ignition coil voltage to frame ground.

The ground lead from the ignition/exciter coil goes through the brake light switches and brake light filament. When the levers aren't pulled, the path of least resistance is through the switches and this is where if flows. When you pull the brake lever, it breaks the circuit through the switches that are dumping all the voltage from the other half wave of the ignition coil when they aren't pulled. This voltage needs to go somewhere so it goes through the filament of the bulb and lights your brake light.

Consequently, if your brake light is out and you pull the brakes, there'll be nothing for the ignition to ground to, you'll lose spark and your bike will shut off. It's a safety feature from Vespa.

Here's a harness for a Grande with turnsignals I use to troubleshoot my bike. Click on the image, right click and select "view image". Then you can zoom in to read detail.

Have you lost your spark? Let me help you find it.

 

STEP 1

First things first. Find your HT coil - this is the box that your spark plug wire is connected to. You should have ONE wire coming into it connected to a spade terminal. Remove that wire (it is likely violet) and connect your voltmeter to that wire and frame ground.

this is what an HT (high tension) coil looks like. Notice the spade connector in the center of the picture.

Next step is to verify your kill switch is working. Turn the bike to "OFF" - you should have continuity (close to zero resistance). Now turn the bike back "ON". You should be showing some resistance or an open circuit. If you have zero resistance when the bike is in the "RUN" position, you've got a short somewhere. You must find this short before the HT coil will spark the plug.

*Note: Make sure you know the difference between open circuit and zero resistance. To see open circuit, disconnect the leads from everything - this display reading is open circuit. Now touch the two leads together while reading resistance - it should go to 0.00. This is zero resistance continuity.
Cool! Your kill switch works!

 STEP 2 

Now, let's check for voltage at the HT coil. Leave the voltmeter connected to the wire going in the HT coil and switch your voltmeter to read voltage. Try to start the bike by turning the engine over. If you don't see at least 3-6volts - it's likely that you won't see spark. If you see less than 1v, you have a weak coil or draw somewhere between your coil and your spade connector going into your HT coil. If you have voltage here, it's likely that you have a bad HT coil. If you have no voltage, please continue.
 If you HAVE voltage, SKIP to STEP 6. 

STEP 3

Next step is to verify that your exciter coil is grounding so it can send a pulse to the HT coil. Find the BLUE wire coming from your engine, disconnect the blue wire (and leave the violet wire disconnected as well). DO NOT connect your volt meter to the blue wire going in to the engine, but instead, connect it to the plug on the wiring harness where your blue wire unplugged from. If you do not have a blue wire, the wire you need to connect to is the one that is not violet, is not connected to violet and is not grey.

Once you have found this wire, set your meter to ohms. Connect to the wire on the wiring harness/the bike that is blue or was connected to blue AND frame ground. You should read zero resistance continuous. Pull the brake lever - you should see a slight increase in resistance. If you do not and your meter reads an open circuit, your brake light bulb is missing or the filament is out.
 If everything here checks out, continue. If it doesn't, fix it, then repeat step 2.
COOL! Everything outside your engine is working as it should... time to investigate under the flywheel.

STEP 4

Time to clean and gap those points! Remove the rubber plug from your flywheel. Rotate it until you can see the points. They look like this:

At this position, the points should be open. If they are not, adjust them until they are. You must loosen the screw and push the points against the points cam to increase the gap - this can be done with a screwdriver. Demonstration here @ 2:15 on how to set the points. You'll need a feeler gauge (or a good guess) and set them to .3-.5mm range and this should get it to run. You'll want to set timing to 17-19* BTDC once you get it running (worry about that later).

Now, lets clean the points. Take a fine grit paper (400-1000 will do) and rub it between the points - you are trying to remove oxidation and crud from the contact surfaces of the points so they can electrically connect. It is much easier to do this with the flywheel off, but you need a flywheel puller.

After the points are cleaned, gapped and still closing, repeat STEP 2. If STEP 2 fails, continue on.

STEP 5

At this point, one of two things has happened. You suck and can't get your bike to pass test two because you suck at cleaning points OR your coil or condenser are bad. The later is more common than the former. So if you don't want to pull your engine out, try to do a better job of cleaning those points and getting your bike to pass test 2!

For this step, you will need to remove the flywheel unless you have an externally mounted condenser. You will not have an externally mounted condenser unless your bike had turn signals. Even so, you'll probably still have to remove the engine.

You will need this special tool to remove the flywheel.

Once you have the engine out and the flywheel removed, you want to test the resistance across the exciter coil. You want this to measure anywhere between .1 and 2 ohms. Open circuit is bad. If you have an open circuit, you did the test wrong, or you need a new coil. So make sure you did it right before ordering a new coil.

In order to get a useful reading, remove the points, condenser and exciter coil from the case and connect the voltmeter to the blue wire/wire that was connected to the blue wire on the wiring harness AND the other lead is connected to somewhere inbetween the coil and the condenser (this should be the violet side of the coil). A good place to connect your second lead is to the solder connection on the coil or to the solder connection on the condenser. Make sure the wire ends are not touching anything.

If your bike passes this test and still doesn't pass test 2, you likely need a new condenser. Replace the condenser and repeat STEP 2.

STEP 6

So, you HAVE VOLTAGE from your violet wire. YAY! If you don't, turn yourself around and go back to step two.

It's time to check the HT coil. Measure the resistance between the spade terminal and frame ground - it should be in the 1-4 ohms. If it is open circuit, you need a new HT coil. If it is excessively high or less than 1, you likely need a new HT coil or have a bad HT coil ground.

Next remove the spark plug wire from the HT coil, or remove the spark plug boot from the end of the spark plug wire and insert the voltmeter lead into the spark plug wire innards to make contact with the conducting filament or screw inside the HT coil the plug wire screws onto. Measure resistance between frame ground and the screw connection/inside of the spark plug wire. This should read in the 10's. If it is open circuit, you need a new HT coil or have a bad HT coil ground. If it passes one HT coil test, but not the other, it is likely the coil and not the ground that is bad.

STEP 7

Test your plug wire and spark plug boot next. Your plug wire from end to end WITHOUT the spark plug boot should be zero continuous unless it's a resistor wire (should be marked if it is).

To test the spark boot, put one test lead on on the coarse threads that thread into the spark plug wire, and one end on the other end ensure you are making contact with the contact that touches the electrode tip of the plug. You should read 5k ohms for the stock boot (it also should be marked) if you read open circuit you need a new plug boot. If you have a different than stock plug boot you may have more, less or no resistance - it should never be open circuit though.

If your meter isn't autoranging, make sure you aren't trying to test outside the range of your current setting.

STEP 8

If your bike has passed all these tests - you have done the tests incorrectly.

If your bike has weak spark and all your zero resistance continuous checks are good, try increasing your point gap slightly. If you increase the point gap so much that the points never close, your bike will not spark. Once you have your bike running, try to find the factory ignition timing and gap specs and set the bike to those.

STEP 9

Ride your damn moped.