Cimatti Gran Prix XL

Gonna make this go fast.

IMG_20201105_135152.jpg

V1 polini with a circuit pipe, polini CP carb, and custom intake.

IMG_20201108_155325.jpg

And hail Satan VIN number.

IMG_20201108_155244.jpg

Re: Cimatti Gran Prix XL

Center bleed Circuit. Welded the stinger to the header for extra strength.

IMG_20201109_103558.jpg
IMG_20201109_110417.jpg

Re: Cimatti Gran Prix XL

Brandon Weiss (Detective brandon to you) /

Whoa, neat. Isnt that going to be unbearably loud though?

Re: Cimatti Gran Prix XL

> Brandon Weiss (Detective brandon to you) Wrote:

> -------------------------------------------------------

> Whoa, neat. Isnt that going to be unbearably loud though?

He could put a slip on baffle pretty easily. Otherwise yeah that's gonna be loud as a motherfucker

Re: Cimatti Gran Prix XL

Not unbearable to me, but the neighbors and cops might not like it.

But yeah, I made it so a silencer can go on it.

Re: Cimatti Gran Prix XL

Upskirt shot

IMG_20201109_120637.jpg

Re: Cimatti Gran Prix XL

Hauls ass. Lotsa torque. Need to upjet, though.

Not sure why they call it an "XL."

It's got a short wheelbase. Might have to do something about that.

IMG_20201109_153312.jpg
IMG_20201109_153212.jpg

Re: Cimatti Gran Prix XL

You dont run fan and cover?

Re: Cimatti Gran Prix XL

God I waant one of these. Bike looks great. Good job on the pipe with the tab going to the head.

Re: Cimatti Gran Prix XL

It looks like the rear could get stretched a little. Those shocks are almost vertical so I am sure you could do a good 3 inches of stretch without it making the suspension too weird. Unless you think the top mounts for the shocks can get repositioned.

Re: Cimatti Gran Prix XL

> Satan 666 Wrote:

> -------------------------------------------------------

> You dont run fan and cover?

Yes, I always run the fan and cover, but I leave it off to tune it when it's a new build. Gotta make sure it's timed, points adjusted, condenser's good, etc.

Re: Cimatti Gran Prix XL

> Jay Rivett Wrote:

> -------------------------------------------------------

> It looks like the rear could get stretched a little. Those shocks are

> almost vertical so I am sure you could do a good 3 inches of stretch

> without it making the suspension too weird. Unless you think the top

> mounts for the shocks can get repositioned.

Yeah, I could lengthen the swingarm a bit, but then I have to modify the fender mounts, chaingaurds, shocks, etc.

Another thought was chopping the frame in half ahead of the front motor mount, sleaving it and adding a few inches of the same OD pipe.

Wouldn't be that hard, but then I have to modify the gas tank mounts and have a gap either between the seat and the tank, or the tank and the headtube.

Then I would have a gran prix XXL

Re: Cimatti Gran Prix XL

> cheetahchrome . Wrote:

> -------------------------------------------------------

> God I waant one of these. Bike looks great. Good job on the pipe with

> the tab going to the head.

Having the tab on the head (and bikes with motor mounts attaching the head to the frame) always worry me. I mean, motors vibrate, pipes flex...

Just seems like a bad combination, but I guess it works or you'd be hearing about problems all the time.

Re: Cimatti Gran Prix XL

> Jay Rivett Wrote:

> -------------------------------------------------------

> It looks like the rear could get stretched a little. Those shocks are

> almost vertical so I am sure you could do a good 3 inches of stretch

> without it making the suspension too weird. Unless you think the top

> mounts for the shocks can get repositioned.

Yeah, the picoli frame swingarms are very short. I stretched mine 3" for more stability.

Re: Cimatti Gran Prix XL

Nice, I just picked this one up for $375

8A35C547-070A-4558-BD02-9721FF9FFFE2.jpeg

Re: Cimatti Gran Prix XL

This thing rips. Never new the power of the circuit pipe. My race bike straight pipe hits at mid-range and keeps punching into high rpms, but this snakey pipe hits right out of the gate. Mellows out on the top end.

Had to upjet the 17.5 polini carb from a 68 (that worked great on my Lazer with a ktm 50 pipe) to a 74.

Changed the gearing from a 10-42 to an 11-38 and it still blasts. Gonna have to GPS some speed runs. Felt like mid 40's with the 10-42.

Pretty sure I have the stock springs in the clutch, I forget. Probably gonna put in some blues.

Forks suck.

First time I hit a good bump brown water squirted out of the boots and it bottomed out. Felt like hitting a curb with a flat tire.

Pulled em apart, dumped out a bunch of water, cleaned them, and they still bottom out, with no way of adding bushings to cushion it.

Probably swap out my Lazer fork legs, but then I need to put sealed bearings in the hub...

Re: Cimatti Gran Prix XL

Nice looking bike... reminds me of a Garelli SSXL except it has side covers kinda like a magnum. I'm assuming these are somewhat rare although two (yours and C3C's) have shown up here in the last two weeks.

Re: Cimatti Gran Prix XL

I wasnโ€™t even going to buy it at first, but glad I did. Itโ€™s a little smaller than the General top tanks I have, but has the same Minarelli V1 that they do. Looking forward to getting it running, bet itโ€™s quick.

Re: Cimatti Gran Prix XL

Throw some porch swing springs over the inner fork tubes. That made the bravo forks on my ciao feel 10x better.

B57310B6-9DFB-404A-B8DA-56ADF4989CC0.jpeg
BB409D6B-50D1-4BE1-9E2C-6C62753B34D2.jpeg

Re: Cimatti Gran Prix XL

Just got back from a liquor store run. Hit 49mph. It's got a little more, but I kept catching up to traffic.

The pipe has insane low and mid-range, but no real top end. Gets to 40 in about a block, and then gradually keeps going. No top end kick.

Here's my ten year old phone converted to GPS speedometer.

IMG_20201111_165639.jpg
IMG_20201111_165644.jpg

Re: Cimatti Gran Prix XL

๐Ÿ‡ฎ๐Ÿ‡น๐Ÿ’ฆ Of the Loin /

fuckin a porch swing springs you say? got a link?

Re: Cimatti Gran Prix XL

> ๐Ÿ‡ฎ๐Ÿ‡น๐Ÿ’ฆ Of the Loin Wrote:

> -------------------------------------------------------

> fuckin a porch swing springs you say? got a link?

Ace Hardware or Tractor Supply . ;)

Re: Cimatti Gran Prix XL

> ๐Ÿ‡ฎ๐Ÿ‡น๐Ÿ’ฆ Of the Loin Wrote:

> -------------------------------------------------------

> fuckin a porch swing springs you say? got a link?

Sometimes the solutions people come up with on here are just too perfect. Brings a tear to my eye.

Re: Cimatti Gran Prix XL

> ๐Ÿ‡ฎ๐Ÿ‡น๐Ÿ’ฆ Of the Loin Wrote:

> -------------------------------------------------------

> fuckin a porch swing springs you say? got a link?

I picked mine up in the hardware section at Lowes, I think they were 15$ for the pair I was looking for springs on McMaster Carr but the price was double for compression springs of that size.

4BD29A5B-91C0-49D3-8459-6B9A45E0FB06.jpeg

Re: Cimatti Gran Prix XL

Sucks when porch swing springs get more attention than my 50mph bike. ;)

nice fix, though. That deserves it's own thread.

But what's up with the cheap bmx tire and rim?

Re: Cimatti Gran Prix XL

Seriously though, 50 is quite a milestone. I think anyone would be happy with that.

No experience with V1's, but if the Polini is like the one for the Puch's, it's probably a ripper!

The paint on there looks kind of like what my HS50 looked like when I got it (also red). Are you planning on leaving it as is for the "patina" or attempting to working to bring it back?

You probably already have a strategy for this, but I had pretty good (not perfect) success with a good cleaning, light rubbing compound to remove some of the oxidation (I can get you the name of the stuff) and then wax. Seems like it depends how oxidized it is and how long it was sitting in the sun...

Re: Cimatti Gran Prix XL

> baird co Wrote:

> -------------------------------------------------------

> Sucks when porch swing springs get more attention than my 50mph bike. ;)

>

> nice fix, though. That deserves it's own thread.

>

> But what's up with the cheap bmx tire and rim?

I was trying a 50/50 bike with all stock motor parts. Figured less rotating mass. Itโ€™s a odyssey hazard double wall bmx rim laced to the sealed bearing front kinetic hub. The bmx tires are a bad choice I learned that getting a flat tire with one. They donโ€™t hold their shape. Some 16x2.25 moped tires fixed that.

What offline gps app are you using for your speedometer? (edited)

Re: Cimatti Gran Prix XL

I'm gonna keep the patina for now. I just rubbed it down with WD-40. Steel wooled the rust off the rims and all the chrome, too far gone to get it perfect, but I want it to look old, not totally rusted out.

Re: Cimatti Gran Prix XL

I use digihub for Android. Really simple, no excess BS. I tested it in my car, and checked it against a radar gun, and another app called Track Addict, that records lap times on the kart tracks I've raced on. It's pretty accurate.

Re: Cimatti Gran Prix XL

Made some floorboards/electronic protectors. Got all the lights working, pretty much done.

I have a new 21mm Polini CP carb that's going on my race bike, it has a 19mm now, and I'll swap that out for the 17.5mm that's on the cimatti now, and try for some more speed. Polini CPs are the shit. Easy to tune, lightweight, and work awesome. Way better than any mikuni I've used.

IMG_20201113_152435.jpg

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account