DRP: Derbi Reactivation Project

[toratora]

Okay hit the wrong button, or the right one too soon. The other fun stuff today.

So the front running light on this bike employs one of these—I think I need to source an LED version as this one, small as it is, seems to be totally down with draining the Shorai!

The little Koso showed up today too—Feel the Speed. I'm totally surprised by the speed considering this came from Asia! But hey that's their slogan. The connections look a bit anemic, but hopefully they'll hold. Maybe put some silicon sealer on there or something. It should also tuck away on the dash nicely.

As for the running of the beast today I tested the 104 main jet. It's better, but there's still enough hesitation getting on the pipe that I'm going to swap it out for the 102. After that I only have one more jet to swap out! I am so looking forward to this bike running properly—it's just going to be so much fun. Yes that CHT says 27°C, and that's in the shade! I feel like I'm wilting But it's getting late enough in the day that there will be more shade soon so I'll finally be able to do some proper wrenching.

[toratora]

If I recall, this is the bulb I fitted -
On the Aprilia they call it the 'city light'

https://www.superbrightleds.com/moreinf ... t-car/207/

But they have a lot of different options. I did all the gauges and turns with LEDs from these guys

Hey RJ—Well I can see the trick is going to be selecting the color least likely to get me pulled over! But damn $13 for one tiny little bulb? Really?

So I'm at a bit of a conundrum. When I dropped down to a 102 it didn't run any better. I pulled the plug and I could see that the tip was silver! Exceedingly lean. It's harder to see in the photos but the same side of the insulator is also more lean than it was with a previous jetting. Now this is with the head that's not the right one. I had to place a bunch of base gaskets in there to get the right squish—which is pretty close to 1mm, which means that all of the ports are opening up about 1mm sooner. Now this could explain the bikes hesitation to get on the pipe.

Of course it could be the timing, as it is possible that I didn't get the ignition timing correct—although I think I did—but I didn't make any offsets for the advancement in the port timing. This all means to me that I have to take a big step back and wait until I can fit the proper head--or maybe stumble upon enough knowledge to put some more puzzle pieces together.

[toratora]

yeah... 13.00 is a bit much. But I'm not the one who is never seen by drivers, either ... <pokepoke>
That said, I've had the back wheel WAY in the air more than a few times ....
Seems like we're both having tuning 'fun', although I think I may have have it a bit easier with a pretty 'known' setup.

Lemme know how I can help ?

that looks way too rich

Looking at the plug I would suggest retarding the timing. Normally the burn back on the center electrode should only be right on the end and perhaps 0.5mm down towards the ceramic, not as much as yours. This could explain the heat factor.

Have you tried dropping the needle at all? Sometimes that flat spot just before the powerband is really sensitive to richness on the needle, you may find just half a clip would help here (make your own shim from suitable metal).

[toratora]

Yesterday I pulled off the kit—it's just never going to work without the right head, and who the hell knows if it will ever show up. I think I'm done with Airsal. Their products are nice enough, but the customer service is horrible. How much stuff do you have to buy from a company to be considered worth supporting? All they had to do was send me the proper head for the kit. I didn't pack the wrong stuff in the box—they did that, and it wouldn't have cost them hardly anything to fix it. I've sent them numerous posts via their website. They never once wrote back. But they did contact Treats about it, and apparently that didn't go all the well either. Here it is well over a year and I still don't have a workable solution.

Tomorrow I'm going to try another kit that I put together from pieces yesterday and today. Greg gave me an engine for the Senda. It came with a ProRace top end, but wasn't running right. Calimari once had some Metrakit stuff on sale—parts left over from their racing days and I picked that up. And a while ago I found some Metrakit rings on teh eBay. The wrist pin and clips are from another kit, but look like they'll work well enough. All the rubber bits are from various kits too.

Yesterday I got out the Swimming Pool Acid and cleaned up the barrel. I also installed the adaptor and temp sensor for the Koso gauge.

[toratora]

Lots and lots and lots of wrenching went down today. We worked hard on three bikes, and it looks like all three will make it on the ride tomorrow.

Here's some DRP pr0n from today.

[toratora]

The bore scope showed up today. I don't have an Android device so I got out the old MSOS lappy, and installed the included software. The scope came with an adaptor dongle that allows it to plug into a regular USB port, and a simple camera app that speaks to the bore scope camera. Basically it thinks of the camera like a web cam, and it looks like the resolution is about the same too.

I pulled the plug and took a look. The camera features six LEDs that light up around the camera. These are adjustable via a rheostat on the little box that is inline betwixt the camera and the USB connector. Knowing the history of the plug this one looks like it's been running lean—don't let the brown fool you as it was there from a time when the carb was setup rich.

But really what tells the story is the piston which shows no wash at all. But the strange thing is that the engine behaves as if it is rich. The EGT and CHT temps were both rather low, and the bike four stroked significantly.

[toratora]

For Derbi de Mayo the bike didn't run very well at all. I have quite a bit of work to do before GPR Camp!

Lost one of the front fender mounting bolts.

The rear hugger was getting caught on the silencer and pulling it off of the pipe. It got very loud when this happened!

I was a bit concerned that there would be an exhaust leak at the cylinder and there was. One of the previous owners had done the mod to allow standard GPR pipes to fit. The ProRace isn't machined for that because they expect you to employ the manifold that comes with the ProRace pipe and it's a flush mount.

I might go a bit stiffer on the forks as it seems to be reaching nearly full travel.

[toratora]

Today was one of those educational days. For instance I learned that you can program a timing light to lie to you. Well not really, but I borrowed this awesome timing light from Ed and it was set to 46° advanced or something. I didn't realize this and was having a helluva hard time setting the timing on the bike!

Making cool stuff. So I wanted a timing disc to help set the timing on the bike. I looked around and thought I can make one of these things. After some futzing about in Photoshop I had what I (thought) I wanted—but really it was a little bit too large. So I'm probably going to be making another one for the HPI mini rotor. I also printed out Matt's setup notes.


I took a holiday card cover and glue sticked the image to it. I then carefully cut it out. This gave me a nice timing wheel that can be held on with a magnet. I then made some markings on the rotor.

After a whole bunch of doing it wrong I slowly started figuring out how to do things like set the timing light, which direction I wanted to turn the plate in relation to the rotor—you know the little things. I think settings are pretty close now, but I'm not confident that the timing light was picking up the true RPM of the engine. So I probably need to connect the MetraKit tach to this bike, and do some more tests. Still I did learn a whole lot today, and feel more confident about being able to properly set the timing.

One trick Ed suggested was to use a separate battery for the timing light. This was a great idea, because then the timing light always had the proper amount of power.

[toratora]

Did another disc, but this one too is slightly too large. This new one is 8cm, the first one is 9cm, I'm probably going to have to make a 7mm to be about the right size.

It was incredibly nice out today and GL came by to show me his new gear. Cool stuff to be sure. D-Boots, A-Star Jacket and pants. All really nice things. Since I had gotten the timing set yesterday we decided to go for a test ride. The bike felt much better with the timing change. I could now go from gear to gear and still stay in the power band. But if you let it get out of the power band you would have to down shift or way a really long time for it to get back in the band, and it wouldn't take much of a drop either. Like let off the throttle just a little bit and you'd have to down shift. It also didn't have as much power on hills as it should have there.

We were just at the beginning of Twin Peaks when I felt a very strong vibration. The previous times I've felt something like this meant a broken frame/engine mount. Plus we saw some water dripping from the radiator—so there might be a leak. I very sheepishly rode the bike home, which meant mostly coasting it down hill. I did notice that the vibration had a very slow cycle, and not really dependent on the rpm, but it wasn't the chassis because with the clutch in and at idle, or with the engine off it's not there. It's going to require some serious looking about.

The engine rotates smoothly, it's all properly tight where it should be, and the compression feels about right too. Just going to have to do some real good looking around.

The exhaust leak is worse, and I'll need to attend to that one too.

[toratora]

Yeah I've been thinking about that—because I had to change things up so much. I think it was a little bit advanced, but not enough. I'm still not sure though because the timing light was offset, and I'm not confident about the RPMs. I've done two things to off set the RPM thing. Matt suggesting using my musicianship and adjusting the bike to the right pitch. Thanks to his help I've already got the Google tone generator set up to do just that! And today I hooked up the MetraKit tach for this bike.

First I had to remove the stock clocks. It's only three self tapping screws but due to my loss of range of motion and strength it took me over an hours to remove them! The reason for removing it is because the tach wasn't function properly.

The replacement unit is a Metrakit tach. It doesn't include a speedo, but it's got a shift light (Yeaa!!), and a temp gauge. For now I'm not using the temp gauge because I already have three other ones. I have the old dash support so I had pre-figured out where I was going to place the tach, but I was to find out that it wasn't going to work there. I had to try all sorts of configurations. Eventually I came up with this setup. Then I connected up the wires. I had to make up another adaptor harness, but it seems the photo got deleted somehow. :/

With that setup it was time to try to figure out what was causing the engine vibration. First I looked at the engine mounts because that's the only thing I've experienced so far to cause this sort of vibration. They all looked good, but I did notice an oil leak at the transmission drain. I'm hoping it's just a slightly loose drain plug and not a gasket leak.

I also checked the pipe too. It's on solidly, even if it does have a bit of a leak!

I didn't see anything that could explain the vibrations. I checked the crank again by spinning the flywheel. it feels tight, smooth, and just the way it should. But if I jiggle it back and forth I can hear a noise. So I think it's either the big end or little end bearing. Using a screwdriver stethoscope it sounds like it might be the little end. Which wouldn't be too bad, but if it's the big end well that's totally going to suck as this crank has less than 100 miles on it.

But it was getting dark and cold so I had to wrap it up for the night.