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Re: Flash 3.2: 72cc Corsa!

Posted: Mon Oct 18, 2010 9:29 pm
by Wheelman-111
Greetings:

OKO 26 mm ordered from Treatland Saturday, here today. I'm stunned!
I want to determine the optimal size for Corsa top end. Maybe I already have it with the 24?
The 30 was clearly too big. But what if the 26 is Just Right?
There oughta be a Law against installing a 112 Main jet in a carb that big, however.

I'm thinking 125 main, 46 Pilot. Maybe 48? Better ideas?

Re: Flash 3.2: 72cc Corsa!

Posted: Mon Oct 18, 2010 10:18 pm
by bakaracer
Wheelman-111 wrote:Greetings:

OKO 26 mm ordered from Treatland Saturday, here today. I'm stunned!
I want to determine the optimal size for Corsa top end. Maybe I already have it with the 24?
The 30 was clearly too big. But what if the 26 is Just Right?
There oughta be a Law against installing a 112 Main jet in a carb that big, however.

I'm thinking 125 main, 46 Pilot. Maybe 48? Better ideas?
On my race bike I have the mhr aluminum which is suppose to be the comp for the corsa .I have the oko 24mmm with a 50 pilot 118main high temp was 409deg air temp 61 humidity 78%. So the 26 I would start with the 50 pilot and 122 main

Re: Flash 3.2: 72cc Corsa!

Posted: Mon Oct 18, 2010 10:54 pm
by Wheelman-111
Greetings:

50 sounds big, but big is Safe, so I'll screw it in...
I'm using a 120 in the 24, so don't mind if I go 125 in the 26?

Last question. If I wanted a little less left-side noise, has anyone sourced an Airbox that

A: Fits the 50mm OKO bellmouth.
2: Can actually be found at an actual Vendor Website that actually exists.
III: Doesn't require the sale of any more Wheel-organs to finance.

I sort of looked into MotoForce in a suburban Montreal scooter shop, but they're out of stock last time I looked.

Re: Flash 3.2: 72cc Corsa!

Posted: Tue Oct 19, 2010 12:55 am
by ottoman
I have been eying up that 26 at Treats for a while now... seems to be the only place that has them.
Looking forward to your opinion on it.

Tormented by Wheel-Demons

Posted: Tue Oct 19, 2010 9:08 am
by Wheelman-111
Greetings:

Now I'm really torn. Respected Z50R_Ghost (Can one change one's Forum name somehow, Noisy?) is reporting good results with his new 21. He says it "pulls just as hard" as his 28 did without the tuning issues in the midrange. Maybe I'm going to waste a lot of time moving in the wrong direction with the 26. The 24 is satisfying the Prodigious Polini Corsa quite well, if still a bit on the rich side... CURSE THIS TUNING MADNESS!!

Anyhow, I plan to give the 26 a try sometime next week. Does anyone have a translation for "Delicate Motorcycle Engines"? That term is printed on all the OKO boxes. :crazy: Sort of like Honda's Owner's Manuals from the 70s touting a "Super-Fine Drive Feeling". :)

Re: Tormented by Wheel-Demons

Posted: Wed Oct 20, 2010 2:11 am
by zuphilius
Wheelman-111 wrote:Greetings:

Anyhow, I plan to give the 26 a try sometime next week. Does anyone have a translation for "Delicate Motorcycle Engines"? That term is printed on all the OKO boxes. :crazy: Sort of like Honda's Owner's Manuals from the 70s touting a "Super-Fine Drive Feeling". :)
Well, Gyro translates to "Great Your Recreation Original". :crazy:

Re: Flash 3.2: 72cc Corsa!

Posted: Thu Oct 21, 2010 2:09 pm
by Wheelman-111
Greetings:

More minor tuning and a slight tailwind yielded 65.3MPH last night. Woo-Hoo! :geekdance:

Re: Flash 3.2: 72cc Corsa!

Posted: Fri Oct 22, 2010 4:50 pm
by Wheelman-111
Greetings-a:

Signore Polini came-a through with another one-a his esteemed-a Go-Slightly-Faster parts:
Polini035_18.6mm.jpg
It's about the same length, but a little bit wider than the Bando 354x18, which I measured at 18.1 or so. This one's at least 18.3, so shimmage will need attention to let the belt ride low in front, high in back.

I've decided you can't tell much about a belt's ultimate potential until a few days have passed - the belt seems to "wear in" and mate better with the pulleys once it's logged a few miles.

This Polini-for-ZX was from MX-Performance, and about $38 with shipping. Considerably less than SIP and all the Euro sources, and arrived inside of a week, despite being back-ordered.

Performance Update

Posted: Mon Nov 08, 2010 9:15 pm
by Wheelman-111
Greetings:

About 300 miles on the Corsa stock crank kit; time for an update.

The cooler Deepinnaharta Texas temps confirmed my suspicions that the 46/120 jets in the 24mm OKO were too rich for the summer heat. The cooler it gets, the better it runs. Chocolatey Plug now looks like Milk, not Special Dark.
Another modest improvement resulted from the loss of the red outer UNI foam cover. I dunno, last night it evidently blew off to join all the other parts I've dropped in ditches over the years... :cry:

Flash now gets to 55 with nearly alarming ease and quickly, on to a best GPS top of 65.3. That's not all she's got, Captain, but I see no point in floggng it since it does all I need it to do, reliably. This morning I wasn't even particularly trying on the Deepinnaharta Freeway, but Garmin-Girl said 63.6. A bit of a headwind - 2 or 5 MPH - and Wheelman don't tuck. Nope, no hill either. Two kicks to start, and only needs choke on the coolest mornings so far - in the 40s.

The best part is the relaxed loping 7.6K RPM part throttle cruising at 40. The steep SEF-type plate working with the Giant 97mm variator and +1000 Blue spring (thanks again for that tip, Bakaracer) make the Power instantly spring to life with a twist of the throttle. The Polini belt rides high in back for sub-wheelie takeoffs but great midrange. Zingg and it's back on the pipe at 9K+ until I let off.

Top speed bragging rights will wait for the next rare down-windy day. Meanwhile I'm diggin' this totally streetable Corsa right now.

Re: Flash 3.2: 72cc Corsa!

Posted: Thu Dec 09, 2010 9:37 pm
by Wheelman-111
Greetings:

Treatland delivered the 10-needle kit this evening.
I swapped in the Baka-san recommended 6KB needle for the K80F that came with my OKO 24.
The 6KB is more tapered; thicker up top and thinner near the tip.
Frankly I couldn't tell much difference, but temperatures ast part throttle stayed low and it's linear and clean.

Re: Flash 3.2: 72cc Corsa!

Posted: Thu Dec 09, 2010 10:30 pm
by bakaracer
so it runs better with the 6kb needle?

Re: Flash 3.2: 72cc Corsa!

Posted: Thu Dec 09, 2010 10:38 pm
by Wheelman-111
Greetings:

Not sure. You know how it is. It's relatively warmer tonight - 50s - but high humidity. I'm not prepared to say it's a lot better, but no worse either.
Still has that cold-blooded stumble for the first half-mile. 46/118.

Re: Flash 3.2: 72cc Corsa!

Posted: Thu Dec 09, 2010 11:05 pm
by bakaracer
that 46 pilot is your problem.

Re: Flash 3.2: 72cc Corsa!

Posted: Fri Dec 10, 2010 12:12 am
by Wheelman-111
Greetings:

46 is too small?

Re: Flash 3.2: 72cc Corsa!

Posted: Fri Dec 10, 2010 1:50 am
by Wheelman-111
Greetings:

OK I screwed the 48 back in. It was too rich in the hot weather, but perhaps not now.
I discovered my Main is a 120, not 118. Needle one click lean from center.