Lets see if we can make a V1 Polini Better

So, to start off many of you read my thread about how one of my Baretta 38s blew up.

If not the thread is here and you can read it.

This is the perpetrating head gasket.

Pieces in the con rod big end.

Luckily I have a stock Minarelli roller crank sitting around so I figure it is a sign that I need to build it bigger. The only problem is that the left hand thread on the roller crank is screwed up from me, so a die is on the way to fix it up. It will also be receiving a new needle bearing.

So, onto the fun part. I was thinking, how can I make this bike way faster and do something a little different. Sadly what I came up with has actually already been done. So I am not going to take full credit for the idea.

This is actually where most of my inspiration comes from. I'm going to be doing the same general thing in that I am going create an adapter to run reeds on the Polini I currently have. Boost porting will also be in order.

As for right now I have been working on improving the ports. So far I had re-done my case matching now that the case halves are apart. Also on the bottom of the Polini transfers there is about a 2-3mm ridge. I didn't like that so I knife edged it to match the case.

Plans:

Lots of porting and smoothing

Reeds

19phbg

Boost ports

Possibly some crazy gearing (that's for later)

Blue springs

Leo Vince pipe

Milled head for high comp

Anyway here are some photos and I hope to keep you all up to date on how this goes.

the right was my first case matching when it was together. I didn't care too much as you can see.

that's all for now

stay tuned.

-Aron

Re: Lets see if we can make a V1 Polini Better

Re: Lets see if we can make a V1 Polini Better

That thread isnt all that bad, you could probably clean it up with a triangle jewlers file. You could go my route and put a puch gila on it. Next go around after the kid pops out is a puch polini....nom nom nom

Re: Lets see if we can make a V1 Polini Better

I probably could clean up the threads with a file but the die was 8 bucks and will be easier and nice to have.

I forgot to add that this bike will be getting K10 hydro forks with sealed bearings and possibly a front disc.

-Aron

Re: Lets see if we can make a V1 Polini Better

Wow that looks really smooth! Post up your tools!

I don't think you even want it that smooth.

Re: Lets see if we can make a V1 Polini Better

post up the specs on that die, size and where did you get it?? I had to cut the nut off my V1 roller crank cause I didn't know it was left handed.

Looks a LOT worse than that though.

Re: Lets see if we can make a V1 Polini Better

The die is 10x1.25 left hand thread.

this is what I bought.

http://www.ebay.com/itm/10mm-x-1-25-Metric-Left-hand-Die-M10-x-1-25mm-Pitch-/110773897917?pt=LH_DefaultDomain_0&hash=item19caa38abd

Still waiting for it to show up.

-Aron

Re: Lets see if we can make a V1 Polini Better

🇮🇹💦 Of the Loin /

https://www.amazon.com/dp/B0007CNJ4K/

is that it?

Re: Lets see if we can make a V1 Polini Better

🇮🇹💦 Of the Loin /

https://www.amazon.com/dp/B0083R5NJA/

no this one

i need one as well because i cut off my nut before learning of its backwards ways

Re: Lets see if we can make a V1 Polini Better

The threads in that one from ebay look worse than the Damaged thread on the crank, like way worse, If that is what mine looked like i would file the flat spot so it will take a nut and just slowly thread on a brand new proper nut, That should take care of it.

Re: Lets see if we can make a V1 Polini Better

I got the die today and it fixed the threads right up! And some more updates. I went to my local motorcycle scrapper the other day to check out some stuff and picked up a reed block. The only thing I know about them is that they say "DH enterprises" on them. The reeds are made of some woven material I don't think it's carbon fiber. It doesn't really matter since I will be replacing them with carbon ones. Also these reeds are BIG, I'm sure they were off some kind of dirt bike.

I am wondering if you are supposed to be able to see light from the other side?

Also I started working on my intake adapter plate. I am in the process of hand filing a nice slope towards the center port.

I also got some aluminum to make my reed housing and I have made various different versions out of card to get it just right. I'm going for lowest profile that will still give good flow. This is not the final version but one of them.

More to come soon.

-Aron

Re: Lets see if we can make a V1 Polini Better

coolness. Have you decided the shape of the port on the inside of the cylinder?

Re: Lets see if we can make a V1 Polini Better

I have not yet. I don't know much about boost ports and reeds so this is sort of a learning process. I learn things by doing them hands on and catch on pretty fast. I was going to pretty much copy the port that the guy did in the thread I posted. Just a single rectangular upward slant from the intake port. Other than that I'm not sure.

I would love suggestions if you have them. I am going to finish the intake then worry about porting the cylinder.

-Aron

Re: Lets see if we can make a V1 Polini Better

So I have updates. I got so into it yesterday that I didn't take a progress photos. Most of these pieces I cut out with a hack saw. To make the windows I drilled holes with my stepped bit and filed them out. It was painstaking but I didn't have a bunch of my tools.

Tonight I am taking them to a friends house to have him TIG the pieces together.

My bench

The bike as it sits right now.

And on another note here is the custom intake I'm making for my girlfriends Bat to fit a SHA to it.

More soon.

-Aron

Re: Lets see if we can make a V1 Polini Better

nice work man!!!, cant wait to see the final product, There was a guy who did something similar on a Metrakit, putting a huge reed block on it, if i come across it i will link it here.

Might give you some ideas for porting and adding windows to the piston or whatever,

EDIT: Found it here easy peasy (edited)

Re: Lets see if we can make a V1 Polini Better

So got some more work done last night on the cylinder. I also got all the new bearings and seals in the motor. I'm still in the process of making the boost port notch deeper but it's progress since I doing it all by hand. I also cut the window in my piston to match the width of my intake port.

I'm going to attempt to make it so the boost port opens just a millimeter or two before the transfers.

Photos:

The whole set-up just barely fits under the frame with some cutting and filing I did.

I made some new reeds from left over polini yellow sheet that I used to make reeds for my girlfriends Bat.

Piston

(edited)

Re: Lets see if we can make a V1 Polini Better

Cylinder

And lastly I bought a 14 tooth sprocket off ebay that has the correct hole for a minarelli and chain pitch. The only problem is that it's too thick so it needs to be machined down. I will probably get the bike running first and then if it has the guts to do it I will mod the crap out of the case to fit it.

That's all for now!

-Aron (edited)

Re: Lets see if we can make a V1 Polini Better

wow dude, great stuff. no way i would have the patience to do that!

Re: Lets see if we can make a V1 Polini Better

Haha....yeah my arms, hands, and fingers feel like they are going to fall off after a few hours of working on this thing.

I'm still deciding on a carb. I know that the 19.5mm clamps style PHBG clone clamps right onto the intake I have since my friend has one and we tried it. BUT I have my eyes on the 19.5 clone race edition for the sake of the race float bowl and screw top.

Any suggestions?

-Aron

Re: Lets see if we can make a V1 Polini Better

looking good, a side benefit is with all that aluminum on top of your cylinder it should help keep temps down..... nice work though seriously by hand, geeze.

I know some people have had trouble with finding the jets to fit the clones but who knows maybe you can sort that out easy with some tappin!!

Re: Lets see if we can make a V1 Polini Better

Yeah I'm worried about building a set up this crazy and then giving a handicap by throwing a clone carb on there...

I'm hoping to have this thing done by the time blood drive rolls around, just gotta get paid so I can buy the rest of the stuff!

-Aron

Re: Lets see if we can make a V1 Polini Better

Did some more work tonight on the boost port, and got it to where I feel satisfied with it.

Just as it is opening

Transfers open all the way

Boost port up close

through the exhaust

View through the back of the piston

That's all for tonight.

-Aron

Re: Lets see if we can make a V1 Polini Better

You guys are nuts...

Re: Lets see if we can make a V1 Polini Better

:P now why would you say that?!?!?

-Aron

Re: Lets see if we can make a V1 Polini Better

Finally finished the filing on my adapter plate. Then I stuck it on the cylinder and matched the intake port. Now it's time for gaskets then I can slap it on there and wait to get paid so I can buy a carb and the rest of the stuff I need.

-Aron

Re: Lets see if we can make a V1 Polini Better

keep going

Re: Lets see if we can make a V1 Polini Better

Haha^ as in finish the build? Definitely. Or port it bigger? Probably not.

So what do you guys think about me widening the boost port? One of my friends is getting on my case to make it bigger.

-Aron

Re: Lets see if we can make a V1 Polini Better

So after talking to other people about this build everyone has me convinced that this setup needs a 24mm carb...? They also said not to bother with Del clones.

SO, I have been looking at the OKO carbs and think that's the route I would like to go.

Here is my dilemma.

I could get the OKO "flat slide" and buy a new range of jets (looks like it only goes up to 200)

Or I could get the round slide that takes Dellorto jets. I would still have to buy more jets but the cool thing about the Del ones is that there seems to be more in between sizes.

What are your thoughts?

Here is one of the ones I am looking at

https://www.treatland.tv/OKO-24mm-carburetor-p/oko-24mm-black-round-slide.htm

-Aron

Re: Lets see if we can make a V1 Polini Better

tm24 only

Re: Lets see if we can make a V1 Polini Better

^that's helpful....

-Aron

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