ESE's works engine tuner

[fixer]

One last post from today's dyno session.

We did a few runs though all the gears, first using the clutch (photo 1) then without the clutch (photo 2). The comparison is in photo 3. The spikes when using the clutch in the lower gears seemed to suggest that the bike was making over 9hp. The conclusion we have reached is that clutch slippage when letting out the clutch allows the engine revs to rise and when the clutch grips, the extra inertia of the rotating engine parts is transferred to the dyno drum and gives it a little bit of extra shove.

9hp looks quite exciting on the chart, but in reality while the clutch is slipping I guess I'm not moving forward as fast, so what I gain when the clutch grips, has already been lost. Oh well.

[2T Institute]

Seems that Euro tuners were onto the pipe step years before Japan Inc 'discovered' it. From a 79 390

[F5 Dave]

Just before we gave up for the night yesterday, we thought we'd try out my fancy new NGK BR9EIX iridium spark plug ($29 from Scootling in Auckland). The BR9ES that was in the bike was of completely unknown vintage and might have been there since the bike was new (in 2002). The results suggest that I can save myself a few bob on spark plugs in future.

But notice I'm still smiling. This dyno business is fun!

Tim

I think you will find the results are conclusive only for that engine in that state of tune. Raise the com any further & you may find the std plugs no longer cut it. Good to see another 50 out there, but time to crank in some decent power & turn a few revs.

[kel]

Good to see another 50 out there, but time to crank in some decent power & turn a few revs.

Agreed. Great to see the enthusiasm Tim but you're never going to get any real performance with the standard setup. Bolt up parts costing less than a thousand dollars will double the power output, considered modifications and testing from that point will deliver nearer 20hp! A few dollars and an expression of talent and the two Daves 50cc reigne may well be over

[ief]

Still don't find the step story complete, it's not only the outlet is smaller then the first dia of the pipe but also the other way around. If one finds the proper outlet dia/ duct volume, why still make the pipe bigger? (thus having a step or as mallosi did a venturi if i get it right?)

Mmmmmmm, moral of the story would be they where on to something but not quit there yet?

[Frits Overmars]

Still don't find the step story complete, it's not only the outlet is smaller then the first dia of the pipe but also the other way around. If one finds the proper outlet dia/ duct volume, why still make the pipe bigger? (thus having a step or as mallosi did a venturi if i get it right?)

Malossi did not do that venturi; I did. The Malossi-text in the pipe drawing means 'for Malossi'; not 'by Malossi'.

...moral of the story would be they where on to something but not quit there yet?

You reckon, if I'm not explaining all of it, I don't know about it, Ief?

[ief]

Malossi did not do that venturi; I did. The Malossi-text in the pipe drawing means 'for Malossi'; not 'by Malossi'.
You reckon, if I'm not explaining all of it, I don't know about it, Ief?

My bad on the first part, missing some subtle (or obvious) nuance here I think, I really don't get what you're saying in the second part, guess I should stick to dutch

[F5 Dave]

Agreed. Great to see the enthusiasm Tim but you're never going to get any real performance with the standard setup. Bolt up parts costing less than a thousand dollars will double the power output, considered modifications and testing from that point will deliver nearer 20hp! A few dollars and an expression of talent and the two Daves 50cc reigne may well be over

My whole bike cost less than that. Bloody chequebook racers

[jasonu]

My whole bike cost less than that. Bloody chequebook racers

Does it make 20hp???

[kel]

Bloody chequebook racers

I havent seen a cheque book in years. Maybe we should call you "Old School Dave",
Quick look on line and the Malossi MHR replica top end kit (not the MHR team) is available for 275 euro's. Bit of a tickle, larger carb and reed block, Frits Overmars pipe ...

[Yow Ling]

I havent seen a cheque book in years. Maybe we should call you "Old School Dave",
Quick look on line and the Malossi MHR replica top end kit (not the MHR team) is available for 275 euro's. Bit of a tickle, larger carb and reed block, Frits Overmars pipe ...

Credit Card Racers?

[TZ350]

This is an old graph but it shows how a pipe that peaked at 10,500rpm can be made to extend the power curve by progressively shortening it.

... a comparison of the power curves of the new long adapter (blue), the new short adapter (green) and the new short adapter with the hose clip fitted (red)
Tim

Frits told us about the trombone, I have simulated it for my 125 and Tim has shown that for his 50, shortening the header dynamically by only 20mm could be beneficial.

Tim, it will be interesting to see where you can get to by developing the porting on the standard cylinder.

[F5 Dave]

Does it make 20hp???

funnily enough no.

[F5 Dave]

I havent seen a cheque book in years. Maybe we should call you "Old School Dave",
Quick look on line and the Malossi MHR replica top end kit (not the MHR team) is available for 275 euro's. Bit of a tickle, larger carb and reed block, Frits Overmars pipe ...

"The MHR Replica 50cc Racing cylinder is the little brother of the 80 MHR variant. The Strongest what Malossi has to offer in the 50's displacement class. 6 transfer and three outlet ports make for enormous gas cylinder change procedures and make this an absolute weapon in the 50cc range"

I still think buying a complete aftermarket cylinder is a grey area. meh. Its not in the. . .damn, almost tricked me into saying it.

[crazy man]

Does it make 20hp???

daves one was always 80cc