Diamo Restoration Project

[bull]

I finally have enough time to start the Diamo Restoration Project that I talked of at the end of the Roketa Restroration Project thread.

Why restore a scooter that was made so many years ago?

These scooters offer the best the scooter world has, they are both hard and open top, plus they have nice trunks, as well as windscreens, wipers, washers, and CD Radios with 4 weatherproof speakers.

If you want to know more search the web or join the Diamo User Group on Yahoo. The gent that runs the group was a former Diamo dealer.

Because of my many years in the auto industry, I believe these scooters offer an exceptional investment opportunity as well as providing sound transportation for the owner. Their import manufacturing life was only 4 years, and there were several variations which provides ample opportunity to acquire a truly unique scooter.

These scooters were part of a movement that more or less failed, because of many things such as:

• Lack of manufacturing consistency.

• Lack of importing company capital to back their efforts.

• Lack of market acceptance at the time, even BMW had a problem with this.
• Lack of service & repair documentation.

Engine offerings started as a GY6 150cc, which was generally setup properly during manufacturing to yield adequate performance characteristics.

Of course many owners, complained of low power, just like most 50cc owners do today and the Chinese manufacturer responded with 2 different 250cc engines. One engine was the Honda Helix clone with 13" wheels, the other was the Linhai with a 10" rear wheel.

These scooters were plagued by electrical problems mostly caused by the alarm systems. This of course angered buyers who had to replace batteries far too often. A solution for this is easily addressed, but many did not know how.

I have taken some photos of the scooter in its current condition, looked it over, prelubed the cylinder and will attempt to start it soon. This first look is just to see that everything can or does work or what needs repaired. Fortunately, I just restored a Diamo with a Helix engine for a customer and found where many improvements can be made.

Later on, I fully intend to upgrade the engine and I think many of you will enjoy my research into that area.

The first look see:

The plastic floorpan is cracked near the center and will need welded and reinforced. The Front body & windscreen mount plate has several holes stripped. The front shock seals are bad and need replaced and shocks rebuilt. Most of the body bolts, screws, clips and nuts are missing. The fuel and vacuum lines have been replaced with the wrong size and quality. The battery is gone. Generally it is not too bad overall. The color I personally did not care for, but it is one of the extremely rare colors and may add to the collectable value.

Feel free to comment, ask questions, or flame.

Here are the starting photos (800x600 px):

[bull]

For the past day, I have been gently hand rotating the engine to distribute the oil and prelube everything.

Today fuel was added to the tank and manually flowed to the carb. A battery was installed, switches were tested and most failed, the horn worked once only, installed a CDI module and bypassed enough switches to crank it over by starter.

The engine did not even rotate a second time before it fired up and roared to life. It immediately burned the residual oil I had placed into the cylinder. After that had burned off, it settled down and runs smooth. It shows plenty of power on the center stand.

After allowing it to run about 15 minutes, had to shut it down by disconnecting the CDI

The next part will be disassemble all the switches and service them. Then start testing all the components like relays, regulators and such.

[bull]

Before starting to disassemble switches for testing / cleaning, I decided to properly repair some of the wires cut by the previous owner. I pulled a fuse block from another Velux I have and momentarily swapped it over to perform testing.

All of the switches work fine, no need to look any further on the switches. Must locate another fuse block or build one for the 4 protected circuits.

Still have two circuits that he cut and bypassed, looks like they might be lighting. One of the wires, brown in color is cut at the wiring connector block, can easily remove the cut wire and resolder, and then reinstall. But the other will take some looking.

It has a Bosch relay substituted in place of the original starter solenoid, will replace that back to original. The chassis connecter for it is melted, might have to splice it into the new solenoid.

The cold enricher was disconnected and the rear lighting had a few cut wires.

After I make these small repairs, it will be time to repair the stripped threads in the front body mount and the floor board.

Took an inventory of the body parts, looks like I have a couple quasi melted rear lights, and a piece of the dash may be missing. The windscreen fortunately has not been cleaned with any chemicals so it is still very clear.

The exhaust system is a little surface rusted and one rubber mount bushing is bad and will need replaced.

[kz1000st]

Isn't it always the case with abused Chinese scooters? Wires cut, things broken and service needed badly? Yet when you cut to the chase the engines run like new and hum. It's how I live with them. Fix what breaks and don't screw around with taking shortcuts.

[bull]

Definitely, owners cutting wires has been the biggest single problem I have seen on any vehicle.

Here is a prime example of why NOT to do that. The brown and red wires were tapped into a green w/ white tracer wire. The green w/ white tracer wire was a switched power feed. The brown wire which was cut from the terminal in the same connector block was a power out wire from the headlamp main switch.

The red wire was an owner installed jump circuit from the green w/ white tracer, to the headlamp connector block.

btw.. the headlamp main switch works fine.

Repaired all the connectors, removed the extra circuit, pulled the wires from the connectors and added heat shrink tubing over the damage for insulation and reinstalled them. Now all that works well and the wires are now re-insulated.

Removed, welded and reinstalled the floor board. Found a few screw clips in the underbelly pan underneath it.

Next is to remove the exhaust and recondition it, then repaint w/ high heat paint. Here is a tip, the black high heat paint sold @ HF gives good protection, goes on well, and does not have a color match problem.

After that I'll reinstall the radio antenna mast, trunk bottom panel, trunk lid. The extra weight should provide a good tilt (see saw action) of the chassis making it easier to remove and reseal the shocks later.

I have been starting and running it at idle for 15 to 30 minutes every day to help it get use to running again.

[bull]

Today, I spent some time plastic welding a few cracks in the lower dash panel, and one mirror mount.

Hung up the trunk bottom, and the bolts thread into aluminum formed nuts on this one. This is not a good design as the nuts could pull thru the rubber mounts, think I'll take some thin flat washers and open them up in the center for the aluminum nuts to sit in. This will keep them from pulling thru the mount rubbers.

Installed the wash fluid bottle and cable tied the wiring loom to the chassis to take the weight off it.

Silly me, I had forgotten that I had a small container of parts the owner had pulled. In the container was the other fuse block, and yes it had cut wires that had to be repaired.

In the fuse block was only 1 fuse. It was a blade fuse.

How about a contest?

The winner gets a DMM like the photo in the Roketa thread (link above). I have a couple new ones, so I'll give one away including shipping to a continental USA address, IF the winner is elsewhere in the world, (s)he pays shipping.

Tell me what kind of fuse it was, and what amperage. Only one guess per forum member.

IF your guess is correct and the first one to get it right, you get the DMM.

[bull]

Today, I pulled the front shocks off, cleaned them, drained what little hydraulic fluid was still there and removed the seals. It is very surprising at how dark the fluid was. Most likely this is from the steel piston rubbing on the Aluminum cylinder.

Simply from this amount of contamination in so few miles, it seems like we should be adding a shock oil change to our Chinese GY6 scooter maintenance schedules.

The seals are sized 30mm x 42mm x 10.5mm. These are the same seals as used in the Honda CR80 bike. The Honda OEM part # is 91255-169-003.

Ordered new seals, made in Japan. Should be here in a few days. Then reassemble, cycle the shocks a few times, drain and refill until fluid is clear.

On a side note, someone wants to sell me a 2008 Machoman 260cc made by Roketa. It supposedly has a Linhai engine and generates 19.2bhp vs the Helix @ 17.0bhp. Can anyone confirm or deny these specs for basically an engine that is only 10cc larger? Just seems like a huge difference for such a small size change.

[bull]

The seals arrived yesterday. Today I replaced the seals and searched for info relevant to the type of oil and quantity needed. Hydraulic jack oil is best used in them. To fill them a level 1/8" below the cap nut required 5 ounces per shock. The springs of course are too strong to cycle them off the scooter.

When I get it off the stand, I'll cycle them a few times and check the level.

[hagedorn45]

If that motor would not have started up what would have been your decision rebuild motor or used motor, working on a burgman an400 2007 down to making a decision to do either or, my first attempt on a project like this but a lot of fun so far. Thanks for these inspiring post

[bull]

First, understand that I believe in serving and repairing as much as possible. I hate to replace a part, if it can be repaired and render a normal useful life. If the engine had not started and diagnosed as a bad engine, I would have opted for at least pulling it apart to find what failed- then replacing that.

Let's assume that your engine has either bad or seized rings causing a loss of compression, which of course can be diagnosed w/o pulling it apart. Also it should be noted that hanging valves will cause low compression, so check them for proper closing before dis-assembly.

I would remove the components necessary to pull the piston for an inspection. Typically, when the rings seize they do some damage to the cylinder (rust), which many times can be removed with a single pass of a cylinder hone w/o increasing the bore beyond specs.

If this comes true, simply cleaning the piston, replacing the rings and reinstalling & torquing restores the engine with almost zero cost.

As to buying a used engine, it depends on when it was last run, how long it has been stored and was it sealed during storage? I don't like buying someone else problems.

[bull]

The past two days I have been installing body parts, which took lots of time for just the windshield. The two wiper studs extend through the windscreen and have a rubber washer to protect from the outside. I wanted to protect the retainers to the w/s mount so I used some black Gorilla tape to seal them before trying to install.




As it turns out the best way to install the windshield is to center the wiper studs through the windshield first then add the rubber washer and retainer nuts, but only hand tighten a few threads just enough to control the position.

Then attach the windshield uprights to the body mount plate with the 8mm bolts and gently tighten in a cross sequence to pull things up smoothly.




Next was test fitting and installing the front body panel. As you recall I thought it was retained to the body by bolts to the mount plate but this was wrong. Those bolt holes are there only on older models (2004). It is interesting to note that 4 retainers are 5mm machine screws and not sheet metal / plastic screws. These are the ones at the inside bottom and about half way up each side.



btw.. there is a difference in Chinese and American sheet screws-- looks like the thread pitch.


I then had to remove the rear body panels to install the top. There are two large chromed pivot that go through the vertical piece with the rear window. These also provide the lateral support through a bar with threaded nuts on each end. The pivots are flanged, with the smaller end going into the chassis.




While I had the rear body panels off, I noticed the left one had a small crack near the top which I plastic welded. During the reinstall of all the body panels, I have noticed that the parts tend to retract, and upon installation it is best to pull them into place by hand and hold them, then install the retainers with enough force to hold them while they reset to the correct positions. This is common to the Roketa scooter as well.

Here is what it is starting to look like:




Was going to reinstall the dash, and noticed that the clear plastic from the factory had never been removed. Removed the instrument cluster, the plastic trim, and the film. Then reinstalled everything.

Pulled the radio wiring harness and you can see from the photo that it has household wiring connectors which is not acceptable for a vehicle, so I will remove them, solder and heat shrink tubing all the joints for a better quality long lasting repair.



The radio in this one appears to be an updated unit as it is capable of playing VCDs and has the RCA jacks for it. There is plenty of room on the dash to add a video screen as well as hanging from the windscreen.

Lastly, here is a picture of the wiring in the trunk and the windshield wash fluid bottle properly mounted.



Have to wait a couple days for the body panels to reset and then I'll install some more.

[bull]

Here is the radio wiring harness repaired. The center terminal of the chassis connector is KAM (keep alive memory) and the other two are switched power and ground. The scooters power to the radio has been tested and works correct.



The radio switched power is fused through the main fuse block in the trunk.