LTH Reed

[Dazza]

By the side of the graph is says RT255, is this a typo or is the CC 255 ? When you say 'correct read' , which ones are you using ? Ta.

I think it is an RT CT
I think Darrells comments are based on the LTH reed

Thanks, I understand that its an MB Racetour but was referring to the cylinder capacity.

sorry, yes I see where you're coming from mate

[J1MS]

On this one i have only cut one central boost, which is angled up to intake manifold area
which is mostly dont forget,all steel.
so it has not gone through to alloy..
even if you cut 3 boosts i still doubt you would go into the alloy anywhere

I will be very interested in your developments on this, rapido with a boost port. I have one I ported about 5 or 6 years ago, a 200 Rapido Classic, but I just havnt been able to put time asside time to get it finished and onto a Scooter. On mine I have the boost port opening a couple of degrees after the main transfers about 0.7mm below the mains in height, have you ported yours to open at the same point, before, or after the main transfers.

[sean brady scooters]

yes on this one the boost is set to open slightly after the main trans,by a very similar amount.

havnt got as far as final polishing/cleaning up and re checking with degree disc yet..

[corrado]

I've recently been having some work done by Broady, and we've tried an LTH Reed manifold. A significant amount of work was required to get the correct reed to sit in, and then some more work to dowel the manifold to the barrel so to avoid any movement as the manifold is made to fit both 150 and 200 variants.

It must be great getting "mate's rates" off Mr. B.

Love those dowels but that's beyond my scope so I'll just drill and tap a 5mm hole in the barrel and hope it stays put.

[cezeta]

By the side of the graph is says RT255, is this a typo or is the CC 255 ? When you say 'correct read' , which ones are you using ? Ta.

I think it is an RT CT
I think Darrells comments are based on the LTH reed

Thanks, I understand that its an MB Racetour but was referring to the cylinder capacity.

its 255cc 71 bore 64 stroke.

[teamv]

I've recently been having some work done by Broady, and we've tried an LTH Reed manifold. A significant amount of work was required to get the correct reed to sit in, and then some more work to dowel the manifold to the barrel so to avoid any movement as the manifold is made to fit both 150 and 200 variants.

It must be great getting "mate's rates" off Mr. B.

Love those dowels but that's beyond my scope so I'll just drill and tap a 5mm hole in the barrel and hope it stays put.

Do you its like air miles ,the more you race the bigger discount you get :bouncyeng:

[paddyfitz]

Had good success bolting one straight on a 70mm asso piston cast iron bore cylinder w/ a krp3/28mm dellorto setup. Cut a window into the piston and had to do a tiny bit of rejetting, but got a pleasantly satisfying amount of acceleration increase across the board. Currently playing w/ a addonv box right now to see if it gets better...
I like it a lot so far...
Anyone else?

[muttonjeff]

Hi Dazza

I've recently been having some work done by Broady, and we've tried an LTH Reed manifold. A significant amount of work was required to get the correct reed to sit in, and then some more work to dowel the manifold to the barrel so to avoid any movement as the manifold is made to fit both 150 and 200 variants.

Anyhow, here's a graph of before and after:


The solid lines show the results after fitting the reed, 27bhp and 20lb torque......... nice !

and a couple of shots of the modded manifold:




I have stacks more graphs, which I'm gonna sort out and post in the correct area later this weekend.

Cheers

Darrell

correct reed, LTH TO SMALL , cheers, art

[drunkmunkey6969]

Popped into the workshop at the weekend and found Sean mid-porting on this Rapido cylinder. This is unfinished, but you can see the work thats been done to add a boost port to work with the LTH reed-valve. I think Sean opened up the LTH manifold as well to match the enlarged inlet port too. I think the exhaust was worked on too (Sean can confirm) and so after a bit of chamfering and poslishing this cylinder was ready to go. The standard Rapido piston was used also, with boost port windows added by Sean.

See pics:












You could also upgrade and use a TS1 piston on this, with wider ring peg gaps, so that the boost port can be made wider......but with the cost of the reedvalve, and then the piston, and then the porting......at what point do you just say......f@@k it....i'll just get a TS1??

[Dazza]

You could also upgrade and use a TS1 piston on this, with wider ring peg gaps, so that the boost port can be made wider......but with the cost of the reedvalve, and then the piston, and then the porting......at what point do you just say......f@@k it....i'll just get a TS1??

Looks good though, that was the dilemma I has was having Dan - would the expense warrant it?
I'm going to go ahead if only to try something different