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Derbi—The Red Power

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toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
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Derbi—The Red Power: Preparing for Installation

Post by toratora » Fri Jun 07, 2019 5:39 pm

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Soon it will be time to install the 075 engine into the Malossi bike, so it needs to be prepped.


It’s such a shame this faux tank was cracked by the wind blowing the bike over. :flushed:


This bike had gotten amazingly dirty under the skirts! :pouting_cat:


I had a lot of trouble cleaning the carb. This one is coming off of the bike, so I’ll have a better opportunity to clean it, but yeah the CP carbs don’t clean up nicely! :grimacing:


I pulled the front brake system off. I have some replacement pistons and seals on the way for the caliper. If they get here in time I'll use them, other wise I'm just going to do a good cleaning on the caliper, as I noticed it was sticking.


This radiator hose will need to be replaced! Fairly quickly it was time to pack things up for the day. Tomorrow maybe the bottom end of the engine can get installed! :paw_prints:
1 x

User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
Contact:

Derbi—The Red Power: More Prep Work

Post by toratora » Tue Jun 11, 2019 3:39 am


I was able to eek out a little bit of time for Project 075. The main goal with this work was to keep from having any shelves that would block the flow from the cases into the transfers. By trimming the gaskets, and performing a little work on the cylinder there should be a nice path for the charge to flow.

2 x

User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
Contact:

Derbi—The Red Power: Cover Up

Post by toratora » Wed Jun 12, 2019 11:39 pm


One last thing I needed to accomplish before installing this engine was to make a couple of cover plates. I did order some oil pump plates, but they wont get here in time.


Because this is an EBE engine it drives the tachometer from a gear on the crank. The bike this engine is going into drives the tach from a sensor on the plug wire. So I decided to delete the mechanism, and replace it with a cover plate. The first step is making a pattern.


Because I don’t have proper tools I cut it with a rotary tool, and then hand filed it. I didn’t plate the mounting hole properly though so it’s a bit off, but it will still work.


Pretty much the same process with the oil pump cover.


The oil pump cover will be sealed, and for the speedometer drive I’ll employ an o-ring. :paw_prints:
2 x

User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
Contact:

Derbi—The Red Power: Adding an Engine

Post by toratora » Thu Jun 13, 2019 9:39 pm


It started out as another warm one! But it didn’t stay that way...


First thing was sealing up the oil pump cover with the coper coat.


Then a little muriatic acid on the clutch actuator shaft to remove the oxidation. Interesting effect of the acid interacting with the dye on the shop rag.


The bike was mostly ready to go, but I had to remove a few more things like the throttle, carb, oil tank, etc., and clean up some parts.


Then I brought the engine out, and set it in place. With the 075 engine it is just enough taller that installing it with the top end on into a Second Edition frame is very difficult. It’s only about 15mm taller, but it is enough to make the job a real pain in the ass, so I decided to fit the bottom end in without the top end. It was much easier, although not with out some issues.


Installing and torquing the engine bolts desu.


Next was to install the kit, which first I decided to instal the piston this time, because the gasket spacer sandwich was going to be messy.


The spacer gasket sandwich of coper, paper and aluminum. I slathered on the coper coat too, as I didn’t want to get a leak!


Installing the multipart head.


Torquing down the head, installing the temp sensor, and ensuring no interference between the cover plate, and the spacer plate.


The intake was grabbed from the Silver bike, and the intake and exhaust were plugged to perform the leak test. Bubbles appears at the intake. Some coper coat was applied at the leak, but this didn’t ameliorate the situation. :scream_cat:


A lot more coper coat was applied, and finally no more leaks! :heart_eyes_cat:




At this point it was cold out, and time to wrap it up for the evening. :paw_prints:
2 x

User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
Contact:

Derbi—The Red Power: Silver Transplant

Post by toratora » Sat Jun 15, 2019 11:39 pm


Due to all the trouble with the Stage6 BR77 kits the Silver bike is going to get a temporary transplant of the engine from one of the race bikes I picked up a few season ago. To facilitate this I needed to procure a cover for it since last year I grabbed the clutch over as a quick fix on the ProRace when its H2O pump failed.


I had the cover from my original GPR’s 075 engine on the table so that became the donor. But just to make sure I wanted to do the H2O pump on it, and delete the oil pump. I had ordered a number of H2O kits from EasyParts, but the order was delayed. I tried to source some 10x24x6 seals locally, but it just wasn’t possible. I went online and found a place called AVX Seals in California that had them in stock and at a good price so I order six figuring it would be good to have some of these seals around. These seals showed up today!


This was the first H2O pump I rebuilt. Back then I also couldn’t get the proper seals. KTM had this wacky seal that was pretty close, and Bob at Scuderia was able to get me a pair of them. They were still working when this cover was last in use last year, but as these photos illustrate it was time to service the pump. The shaft had grooves worn in from the factory seals, and the KTM seals. For this repair I employed another shaft from a pump that was serviced, as it didn’t suffer from such wear.


With the parts all cleaned up it was time to assemble.


I will need to make a proper cover plate eventually, but I didn’t have time today so I employed a temporary plug, The clutch lever arm needed a bit of clean up work as well. I also cleaned up the intake manifold, but I decided to install that once the engine is in the bike to make it easier to install the engine. :paw_prints:
2 x

User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
Contact:

Derbi—The Red Power: Where there is Two Stroke Smoke there is Happiness

Post by toratora » Thu Jun 20, 2019 12:39 pm

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So much wrenching going on!! :grimacing:










So many little things that have to occur to get a bike together!


Huzzah!! The ritual smoke of good tidings!! :paw_prints:
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User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
Contact:

Derbi—The Red Power: Braking Good!

Post by toratora » Thu Jun 20, 2019 12:39 pm

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Now that the bike could finally go, it was time to work on making it stop! :scream_cat:


EasyParts or Maxi had a sale on an AJP master some time ago. The lever wasn’t correct for the GPR, but I figured eventually there would be an opportunity to employ it so I bought it. The price, as I remember was less than an AJP master rebuild kit! :kissing_cat:


The GPR master has some adjustability not found with the other one, but as it turns out it’s just the lever design, and by swiping out the lever and pin I was able to employ this master on the Malossi bike.


The caliper however would require a bit of work to become functional. I had noticed the front brake sticking a bit. This is usually caused by dirty pistons. I found the snap ring pliers worked quite well for extracting the pistons. I would be nice to have the proper tool for this job! :grimacing:


Sure enough these pistons were dirty, but the cleaned up quite well. I have new pistons and seals on order, but they weren’t here in time for this procedure. :crying_cat_face:


I couldn’t get enough torque on the back caliper bolts with it off the bike so I had to put it on the fork in order to get enough leverage. It took forever to bleed this setup. I replaced the crush washers multiple times, and a number of other little things.

What seemed to work was removing the caliper, and squeezing the master lever until the pistons came out nearly all the way. Then Pushing them back in just enough to get the caliper back over the rotor. Then I could get proper pressure.

Still the lever is coming too close to the bar making two finger braking impossible as the other fingers impede the lever pull. I’ll be putting some more effort into this to find a solution.


While servicing the front brake I also took the opportunity to repair the front blinker. :paw_prints:
1 x

User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
Contact:

Derbi—The Red Power: Silver Transplant II

Post by toratora » Thu Jun 20, 2019 2:39 pm


Back to wrenching on the Silver bike. This one is going to go lightning fast—very few photos!


First was pulling out the engine.


Getting things in place.


The intake was the last thing I was able to attend before having to wrap it up on this one. :paw_prints:
1 x

User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
Contact:

Derbi—The Red Power: Silver Transplant III

Post by toratora » Thu Jun 20, 2019 3:39 pm

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The Silver bike makes it back on the road, but not without some hang ups along the way. After getting everything installed the bike wouldn’t start, and as it turned out the issue with with the ignition module. With that replaced the bike started right up, but the carb was acting very strange running the bike at much higher RPMs than it should.


Pulling the carb revealed a lot of corrosion.


I had a special float bowl with a quick access port for this carb, so I swapped that out. Then I cleaned out the rest of the carb. Also noted that the idle jet is a 45, and the main is an 80.

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With that the bike was running great!! Time to put the skirts on!! :paw_prints:
1 x

User avatar
toratora
Posts: 3161
Joined: Wed Oct 11, 2017 1:05 am
Location: San Francisco
Replica: Derbi GPR
Cagiva Mito
Cobra CX65
Aprilia RS50
x 1768
x 1977
Contact:

Derbi—The Red Power: Malossi!!

Post by toratora » Thu Jun 20, 2019 4:39 pm

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You’d think I would have tried to get a Malossi kit for the Malossi bike. :hugs: Oh well the BRK is what seemed to be the most likely solution for the Project 075 solution, and so far it appears to have been a good choice.


I noticed a fuel leak which turned out to be the need of a clamp on the fuel line. The clamps I had didn’t fit so a zip tie was employed.


Then it was time to install the plastics. I had a heck of a time getting the lower tail section piece to fit in thanks to the little ride that Matt took on the bike. But eventually I was able to overcome, and get it in place.

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Later I took it for a test ride. I should have gotten some photos! But I was lame. This was the bike’s first run after a couple of heat cycles, so I took it easy. The more I road it the stronger it started to get. for an experiment things seem to have worked out quite well. This is likely to be a very fun riding bike. I did notice that the tach was incredibly clear. I reach out and found that the cover had completely fallen off. It’s a never ending story... :paw_prints:
1 x

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