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DRP: Derbi Reactivation Project

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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
Contact:

DRP: Modulation

Post by toratora » Fri Dec 18, 2015 3:39 pm

Have you ever been hit by a cager? I have multiple times. Every time they claim that they didn't seem me. Now this wasn't me riding like some crazy person. Each time I was just riding down the street, and they ran into me (plenty of times I've successfully avoided getting hit too). The common denominator was they claimed to not see me. Other riders that I've spoken with have stated that of all the things they've tried from hi-viz vests, to loud pipes the only thing that has made any real difference was head light modulators. Federal law does permit these--within some rather strict conditions. These things tend to go for about $60, and we'd have to mod them to work on our goofy bikes. But could one build one? hmmm. So I did a little searching.

I found this page with a pretty nice design. The two issues with this design is the need to have a photo cell switch to turn the device off at night, and that it modulate at 4 times per second (240 per minute). I probably have enough knowledge to add the switch, but I'm going to have to do some learning to figure out the timing. Looks like fun. ;P

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This video illustrates how well they work. Skip to one minute mark to see the head light action.


Now there is some risk to riding with a modulated head light. Lots of cops are unaware of the law. This shouldn't be a surprise to anyone that's been around the block. There are just too many laws for a cop to know them all. So it would probably be a good idea to have the federal law printed out, and stashed on the bike in case you get pulled over. And remember a cop can legally fuck with you if they are ignorant of the law.
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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:

DRP: More Flow!

Post by toratora » Fri Dec 18, 2015 9:39 pm

Stopped by Treats to say hello. They had just gotten in these new fuel filters. Super cool, come in lots of colors, and they are rebuildable too. The neat thing is the flow hole on the red one is actually larger than the one on the OMG filter I had previously picked up for this bike. Also, it's more red bling for the bike. :)

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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:

DRP: Teh Fibaaaa

Post by toratora » Mon Dec 21, 2015 9:39 pm

I should probably wait a while to post this--like once I have it actually mounted on the bike, but ah, well...

There's a bit of a story that goes with this little treat. My friend Greg got me checking out the Tyga website. I noticed that they make some parts for an Aprilia, but the model number didn't actually exist (RSV125). With a bit more investigation I figure out what they really meant was an RS4. I packed that knowledge away for a time when it would become relevant.

Later on the KTM 390 list one of the guys, Matt of Formula 390, announced that he was becoming the US distributer of Tyga KTM 390 parts. I inquired if he would be abel to get other items. He said he would check into it for me, but that it wouldn't happen until he made another big order, and that would probably take a long time. That long time was incredible short!

While I really wasn't prepared Matt made it easy enough that I could actually get the part that I had figured would work on the Wicked GPR. This was a short time ago, and today it showed up. :)

I apologize for the bad photos. Eventually I'll get some with proper lighting. :P The unit itself is absolutely gorgeous. Tyga's fiber guy is amazing.

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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:

DRP: Of Being Silly

Post by toratora » Sat Jan 09, 2016 9:39 pm

Been cleaning house so I thought I'd stick the GPR up on the coffee table for a minute. :lol:

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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:

DRP: Malossi F38 R

Post by toratora » Mon Jan 25, 2016 9:39 pm

Today I have something really special to share. I've had these since July, but was hoping to get them installed on the bike. I've been holding off on the installation until I get the fairings worked out. I'm actually surprised how long I've been able to keep these a secret. :eek: But it's time to let this cat out of the bag. I use to think these were unobtainium. Then Benji was able to get them for me. So if you too would like a set ask Benji over at Treats--Thanks Benji. :)

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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:

DRP: Kaneban Top Bridge Kit

Post by toratora » Wed Jan 27, 2016 5:39 pm

Found this on a Japanese site. Probably wont be getting one of these, but for you cats with the newer front end Derbi/Aprilia replicas check out this triple tree top piece. These are about $450 with the current exchange rate.

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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:

DRP: Changing of the Plan

Post by toratora » Wed Jan 27, 2016 9:39 pm

A couple of things have happened that have influenced me to change my plans a bit. I haven't been successful in getting the 04 farings to fit on the 05. The 05 is a bit larger. Aprilia was able to take the RS125 farings and put them right on the bike. Those farings do look a little bit too large once you know that's what they did for the GPR-RS. Also, now that I need to source some parts for the Silver Bike I might as well use these parts on the Silver Bike, and order up the fiberglass bits for the Black Bike. :lol:

I'm also going to put the Jolly Moto on the Silver bike (for now). I have two other exhausts to run on it but I can't find the manifold for either one. I contacted Arrow for a replacement, but they no longer have them. I need to see if Metrakit makes one available for the Prorace pipe. I've also got to look into getting a proper sized pipe for this Airsal Xtreme kit.

Hopefully tomorrow I'll make it over to Speedy's, and get the nice new front rubber put on the bike. As a place holder I put the 04 wheel on the bike. :)

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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:

Re: DRP: Derbi Reactivation Project

Post by toratora » Thu Jan 28, 2016 9:39 pm

Rumenicestak posted a video of the Sava MC50 M Racer Super Soft tires. I have the front one that I got from Benji. Hopefully today I'll get that mounted. Still waiting for the rears to make it to the States.
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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:

DRP: Tire Shapes

Post by toratora » Fri Jan 29, 2016 9:39 pm

Sava recently came out with the SuperSoft version, and I'm still waiting for the rear super soft to show up at Treats--it's not even in their store yet. I have the front, and it's sticky. Made from the same compound (at least that's my understanding) as the Sava slicks. I put the Sava slicks on the track bike, and the are confidence inspiring! I'm sure your dad is totally enjoying them, right?

The thing about the MC50s though is that if you run them on the older bikes you wont get the proper profile. Those bikes should have a 90 80 17 up front, and a 110 80 17 in the rear. If you upgrade your wheels to the 2005 for the GPR, and 2006 for the RS50 then the MC50s will fit properly because those wheels are set up for 100 80 17, and 130 70 17. For the older wheels the MC18s are the tires to run. I've got these on the Silver Bike and they are very nice too.

You can run larger tires, but there's a cost--due to the different profile. If you look at the photos of the Black bike I've gone too large with those tires. I did this because I wanted a really good tire on the bike (and I was planing to run the 125 2T rear wheel which is wider). Bridgestone makes their GP-street tire in a 110 70 17 in the front, and a 140 70 17 in the back. The back is a multi compound tire! But because these tires were too big for the newer wheels the profile was wrong. The wrong profile will effect the handling. In our cases you get a rounder or more U shape rather then the the more V shape that you'd get from the proper size. This makes the bikes turn slower. Which is fine if you like riding the Super Slab, but I prefer the twisties. ;)

The big issue for this though is that when you are in a corner with the U shape you have a smaller contact patch than you do with a more V shape tire. Contrary to the belief that a wider tire will give you a larger contact patch it actually (on the wrong wheel) will give you a smaller contact patch in the corners (where it's important). So unless you are drag racing getting the proper size tire will allow you to go faster in the corners.

Here's an illustration

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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:

DRP: Kodak Moment

Post by toratora » Fri Jan 29, 2016 11:39 pm

Sometimes you just have to take a photo.

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