Posts Tagged 'gpr'

L’s magnum and some laguna stuff!

a while ago i got L’s magnum up on my lift to pull apart the transmission and check out the shift pucks. the bike has 201 miles on it, but it has been sitting for many years and i didn’t want to just assume they were still in good shape.

well, they totally were.

everything in there was in great shape. totally not suprised, the whole bike is clean and in good shape. it was just one of those better-safe-than-sorry things.

besides, i still had the low mile PAZ pucks that were removed from sparkle butt when the prototype atomic pucks went in. since i had this thing opened up, i figured i’d throw them in.

i threw on a new clutch cover gasket and sealed everything back up and topped it off with atf.

since i’m putting this thing back on the road for L, and this is pretty much her first real 2 wheeled ride out side of bicycles and the hobbit she rode around for a bit, i am making it as little and compact as possible. i decided the rack had to go (though i’m keeping it so that it can be thrown back on for possible camping adventures or whatever) and the rear fended needed bobbed so that the tire was the thing that stuck out the furthest.

first pulled the carb to run it through our ultrasonic cleaner. it’s always a good idea to get that going while you’re doing other stuff to minimize sitting around time. while the carb’s cooking, i can take care of little stuff.

new fuel line, fuel filter. stuck a drill to the crank and turned it over enough to make sure the oil pump is pumping as it should. replaced the starting cable.

pulled the rear fender off and removed the tail light, then kinda eyeballed where i wanted the fender to end, rolled the fender back and chopped off the front of it to retain the stock lip on the rear (and keep that sweet ‘the marvelous moped’ sticker intact).
the carb was done by this point, so i rebuilt and reinstalled it.

i picked up a little led tail light for the rear. i think the stock lighting coil should run it ok? we’ll see. i haven’t mounted it up yet, because i’m still trying to decide if i want to drill holes in that perfect trunk or not. i did run the wires for it, though.


with the carb reinstalled, pump working as it should and a new sparkplug thrown in, i hooked up a fuel iv and fired it up with my drill. the thing started right up and proceeded to smoke out the whole 2nd floor of our building. it was awesome.

i’ve since installed a new petcock after unsuccessfully rebuilding the stock tap (i can’t find a proper rubber piece for it) and replaced the left hand grip. i also pulled the pipe apart and cleaned it out as best as i could, but it’s still pretty smokey.
i need to get some brake knarps, trim up the stock brake cables and then i can go ride the thing around and hopefully burn out the rest of the junk in the pipe.
then it’s a matter of wiring it up proper and getting the plate for it and L can finally start ripping it around sacramento!

in other news, the kickstart guts for the laguna’s gpr engine finally showed up from europe!
so i pulled the clutch cover on that engine and went to work installing the parts.
it required me to remove the clutch itself, which i wanted to do while i was in there anyway. the clutch pads look alright, maybe a tiny bit worn. i think they will be fine for now. also, it’s got yellow springs in the clutch, i have no idea if those are stock or not.

everything where it goes.

i don’t have a replacement clutch cover gasket just yet, so it’s not quite ready to go all back together, plus i need to fix some shady stuff the previous owner did to this engine. for example, see those marks on the clutch’s face plate? they are from the oil level bolt being replace with one that was too long, it was dragging on the clutch. how do you not notice that?

i also remembered that the previous owner had said the cylinder had some porting done to it. i figured now was as good a time as any to pop the top off and have a look. the porting is actually pretty ok. everything looks clean and nothing looks horrible. i’ll run it as is.

i bolted the engine back together loosely until i get new gaskets for everything, and put it aside. i hope to be able to afford to get the parts sometime soon, it would be awesome to have that bike on the road this summer at some point.

but then, i have so many project sitting up here..

new front for laguna gpr pt.2

today was a super unproductive day. kind of a bummer. i did stop by treats and picked up some tires and the fork legs for the laguna, however.
i didn’t get any pictures of putting things together, it really wasn’t that exciting or picture worthy. i just pulled the triple from the frame and cleaned up the bearings, re-packed them in grease and put it all back together.


i decided to use ebr headlight ears instead of the derbi ones. they are pretty rough and don’t fit tight on the fork at all. who ever put it together last time used some goo to keep them from moving around too much on the fork legs, and that shit was a bitch to clean off. i’m pretty sure the headlight ears will be mostly covered by the dash anyway, so whatever.


figuring out wheel spacers was a bitch. i don’t really have the means of cutting precise spacers at the moment, so i just collected a bunch of various spacers for this size axle and got it as close as i could. as you can see above, it’s pretty darn close.

i’m not super stoked on the brake rotor spacing. it sits really close to the wheel and pretty far from the fork leg. i’m not exactly sure what i’ll be doing about that just yet. i want to do some work to that rotor adapter before this thing is done anyway, so i’ll figure it out later.



the stock axle was way too long. i found a shorter one but even that was too long, i had to use spacers on the outside of the fork legs too. super ghetto. i’ll be ordering up a proper axle and some spacer material to do the whole thing right.

tomorrow i’m moving to sacramento. i got a 3 bed room house with a detached garage with an added on shed thing and a back yard for $100 less a month than i pay for my super crappy stuido here in sf. my commute is going to suck, but it’ll be worth it to have a nice place finally.
my buddy ryan has a welder and a compressor he’s going to let me use, so i should be able to finally move forward on a few of these projects. i’m pretty excited! i hope to get something finished soon!

new front for laguna gpr pt.1

i was able to throw the laguna on my lift today. i’m picking up some puch magnum hydro ebr fork legs tomorrow from treats, they are the same diameter as the stock laguna legs and will go right in the tripples.


the disk brake set up is pretty interesting. it was a good idea, but kinda poorly executed. who ever did it made an aluminum cylinder that fits pretty snug in the brake drum area and bolted it to the wheel using three allen bolts. then the disk itself is bolted to the other side of the aluminum cylinder.





the threads for the bolts are all just tapped into the aluminum and not in the best shape. i will probably drill them out and use helicoils to get some good steel threads in there. also, i’m a little concerned with those three bolts being stout enough to not ever snap, so i may swap them out with some higher grade stainless bolts, maybe even replace them with a larger size.
i just realized i didn’t get a picture of the back of the wheel with the disk adapter out, but the three bolt holes have been drilled through three flat spots similar to the five spots you can see on further out on the back of the wheel.
does that even make sense? whatever.

also, the stock fork legs are for sale if anyone wants them. get at me here if you want them. they have been rebuilt not all that long ago and the fork lowers were powdercoated black. i would replace the oil and put crush washers under the drain bolts on the lowers, as there should be some there but there isn’t. they were leaking.


no rust or pitting anywhere.


this is where i left it, i think i’ll stop by treats and grab the forks along with some other goodies in the morning on my way to work and throw them in first thing. it’ll finally have a proper caliper mount!



so it’s time for the laguna’s piston port to go.
every bolt holding that engine in was loose and covered in oil. the pipe was barely on there. this bike has had issues in the past with loosing exhaust nuts and i can see why, there’s not much room in there to get a wrench on anything! i would use those long allen nuts on this thing if i were going to keep the engine.

having never removed the engine from a laguna, i didn’t realize the swing arm pivot bolt had to come out, and that the kickstand/rear engine bracket thing was all together. kinda neat? anyway, it all came out easy enough.

new lump next to old lump. the gpr engine is quite a bit shorter.

i set the engine in the frame to get a look at things. it fits nicely! this is going to be a piece of cake! with some simple plate brackets welded to the frame the engine will go right in. sprockets line up perfect.


the engine is sitting in there a bit more forward than it will when it’s mounted i think, i have a ton of room to put it where i want to.

so yeah, the engine with the puch gila kit, custom atomic mopeds intake and derbi pipe modified to fit the gila are all up for grabs. i’ll probably post it in the buy/sell on moped army soon, but friends get dibs (if you reading this i consider you my friend! probably).
also up for grabs are the laguna plastics. the left hand side plastic has the bottom tab broken off, but i think the tab is still bolted to the bike, so one could possibly plastic weld them back together.

the engine looks right at home in the laguna. i love that it says derbi all over it too, once it’s all mounted it’ll look like it came this way from spain.

derbi laguna gpr

i moved my tool box upstairs into the moped shop area which allowed me to finally rip the engine out of the gpr. i didn’t get any pictures of that, but it was a bitch. remember the first time you tried to re-install the engine in a ciao? how frustrating and impossible that was? this was like that, but worse.
then i realized i was doing it wrong and the dumb thing came right out.

i put the gpr in the corner and put the laguna up on my lift. that’s where things sit at the moment, but i think i’ll go in tomorrow and pull the engine out of it. it’ll be up for grabs if someone wants it, along with the pipe and probably a few other laguna goodies! get at me and we’ll talk money!

the piston port moped engine is quite a bit longer than the gpr 6 speed lump, which means it should go in relatively easy with extra room inside the frame for the radiator.

some preliminary plans include a hand made sheet metal tail section that may include the exhaust baffle, possibly hand made sheet metal tins for the sides, and maybe even a mini fairing, similar to what it already has, but not broken and awkward.
a nice fork will be in the works, with a better front brake, maybe some handle bars instead of clip-ons. we’ll see!

oh man, i have so many fun projects going on!

i’m parting out my gpr70

i bought this thing for like $300 around a year ago and never did squat with it. the engine, cooling system and possibly the fork are going on doug’s laguna, the rest is up for grabs.
i have all of the parts for it, minus a few little things i think. a friend is interested in all the plastics, so those might be spoken for. 16″ wheels, frame is titled.
i’ll get pictures of everything as i’m pulling it apart, but if you think you want anything you can get at me now. shoot an email to or just leave a comment here.

enter your email address to follow this blog and receive notifications of new posts by email.

Join 121 other followers

  • 26,201 yous guys