Hey Ron, Tell Us About The Avanti TT Kit?

[soulsurfer]

Sorry guys I have to get back to work as my cylinder heads only arrived to day and I still have loads to do, just copied this, will be back later to answer anything as long as it is not too difficult!


MWO Transfer Ports, why the name? had to call them something, the way the transfers loop over the two barrel studs "looks like a letter M W for wrap O for over hence M Wrap Over Port (MWO Port).

Unique? I thought it was, definitely is for a Lambretta but according to Harry Barlow, he tells me that many years ago Yamaha did something similar. But seeing as I have been in hibernation for the last 34 years I would not have a clue.

So How does it work?

First I will tell you how it came about, Most kits these days have 4 transfer ports but I could not do this as the Exhaust port being bridged is too wide to accommodate extra transfers as the barrel studs are in the way. anyone that has an RB 225 will see that the left land transfer has a small "notch" in it to get around the barrel stud!

So I just had to think of a way over this, hence the MWO.

The name TT3 came about because it looks like 3 transfer ports but in actual fact there are 2 coming into one window, both curved so they do not crash into each other.

Adam has given you a some insight, but in very layman terms this is what happens:
when the piston is at Top Dead Centre the inlet port is and has been open whilst the piston is traveling up the bore, closing the transfers on the way.

If you imagine that you have something like a vacuum which has been created, the new fuel mixture rushes in and fills the crankcase and transfers. It does not matter if the new transfers are longer as they are always filled.

On the downward stroke the piston pressurizes the crankcase and the fuel mixture is forced out of the transfer ports.
The pressure being the same will release the mixture with the same force on all 4 ports.

The difference with the MWO Ports is that they are all operating at the same pressure and for a piston ported kit it is about the best you can get it. If I was a mathematician or could tap up one of the Japanese I could get it better.

At 5,000 RPM the inlet port on this kit is open for 0.00533 of one second, how much fuel mixture can get into the bore? Anyone know? I thought I could work it out but there are positive and negative pressures to consider and it blew my mind.

Not much change there then!

Hope this helps

[Andy Pickering]

http://scooterotica.org/forum/viewtopic ... 3&start=10

Try to keep up Mike..

[soulsurfer]

I saw that, which was why I copied it word for word to make the subject matter clearer

[Muppet]

what pipe and carburettor are recommended for the kit; would it work with 2/22 and af clubman,

muppet

[Muppet]

meant to ask; any plans for a small block version; same thing but smaller cc "high torque small block" better cooling etc

[OAP]

"what pipe and carburetor are recommended for the kit; would it work with 2/22 and af clubman",

Better to use at least a 28mm or larger, It will work with a 22mm but to be honest I have not had time to set one up and try it. It will obviously be a lot slower on acceleration & I would definitely not use an air filter with one.
Exhausts, is all down to what you want to achieve. It has turned out to be very versatile,I have tried various set ups.
I have used a Franspeed Race with a 4.8:1 box with a 30mm VHSH, on the local By pass it goes off the clock with ease.
I have this last week put a new old stock Dellorto 30mm VHB with a Taffy copy, not slipping the clutch to move off it just goes. I am having to get some studs made for expansion boxes for the two piece brackets to the main engine case. They are normally fix with 2 x 8mm bolts & nuts but the bolt heads touch the fins in the cylinder. I expect Andy Francis will get this sorted soon I hope. 42mm Clubmans & standard 48mm could be an issue as the do not release the gases quickly enough.

Avanti 48mm Clubmans, unfortunately I have cleared AF out of their Indian boxes for converting and I cannot find any at the right price, so I am going to have to look at getting the whole thing manufactured but funds are somewhat tight at the moment. Using my box it does fly now I sorted the jetting out.

I will give some info on Sunday, I'm a tad busy until then.

""any plans for a small block version""

All ready, but I must sell at least 300 large block first, all down to money, without my time and general costs and overheads just to get to this point has cost 48K so unless the response is good, it will not happen.
A 186 will be up to at least 20 bhp minimum

Ask what ever you want and I will catch up on Sunday, someone my have one going over the weekend, couple of guys are picking theirs up tomorrow.

[RICSPEED]

what pipe and carburettor are recommended for the kit; would it work with 2/22 and af clubman,

muppet

get yer coat dude

[soosh]

Hi Ron,was the jetting spec with the Avanti pipe different to when I took it out?
If so,I take it goes even better now?
Cheers
S

[Muppet]

if I fitted the avanti with a 30 mill and a ron Moss 48 pipe; on a standard tank what would be the maximum range I could expect;

muppet,

[OAP]

""Hi Ron,was the jetting spec with the Avanti pipe different to when I took it out?
If so,I take it goes even better now?""

You took it out with a welded up piston! Distorted! Carb not jetted in correctly as not the right atomizer, with that set up it made 24BHP on Diablo Dyno, does it go any better now?


"if I fitted the avanti with a 30 mill and a ron Moss 48 pipe; on a standard tank what would be the maximum range I could expect;

muppet,""

About 500 meters,

With the new cylinders & pistons ( only arrived last week) I have not had chance to go on a long trip & will not be this week on next. On my knackered piston it was doing 70 miles thrashing it