ESE's works engine tuner

[TZ350]

.

Speedpro told me he got an extra 2hp when he fitted a good central sparkplug head to his Suzuki TF-NSR125 special.



Today we binned the NSR head (blue line) and fitted a VHM central plug head (purple line) and got an extra 2 hp everywhere. Shows what can be done with a good combustion chamber shape.

[F5 Dave]

Despite the peak revs being 500-700 rpm lower. Nice.

[TZ350]

Despite the peak revs being 500-700 rpm lower. Nice.

Yes, no other changes so not sure why that is ..........

[husaberg]

Glen, nah, no need for a solid model for the CNC, I'll just make one on the pattern bench. I have a set of 175 cases cast up but with no balance shaft provision. Or provision for s second rotary valve case on the other side. And the gearbox I've modelled it around might be on the light side.
Back to the old whats best for a gearbox. Must have wide even gear spacing (WR) , robust (not Honda), cheap and readily available.
I'd just about choose a 350 Kawasaki gearbox, I have a few, they just don't break, but there change mechanism is a bit Heath and Robinson. So perhaps not.
Suzuki ? Were their gearboxes any good? Can't really go to the wreakers any more and sift through the bins, like the old days.

Use a Vt250 gearbox nice ratios strong gears quite narrow, millions made available from any wrecker in any country. nice clutch, available in 5 or 6 speeds as well. also the same gearbox is used on the MVX250 an fthe CBR250
they have an intersting gearshift set up though almost planetary. available either push or pull left or right clutch.

[wobbly]

More com or higher msv , both do exactly as the graph shows.

[diesel pig]

Wobbly I was looking at the Superfinishing farsebook page and saw a picture of you and Dennis Charlett's 400. I was wondering wither you had the crankshaft done as well as the gearbox? I was thinking not just from the reduced friction point of view but also the improved surface providing a better seal for the crankseals and longer seal life?

[F5 Dave]

You'd think that the oil film would do that and not care too much for the details beyond smooth enough to keep a film without poking through. Maybe.

And how the hell are you?

[Pursang]

More com or higher msv , both do exactly as the graph shows.

If comp or squish haven't been changed, could the central plug create a faster & more efficient burn, and be producing higher pressure quicker.
Perhaps retarding the ignition could be tried, not for pipe heating, but to reduce the higher pressure occurring before TDC.

cheers, Daryl

[wobbly]

Denis's 400 had all of the gears done , and that included the primary gear seal surface.
I didnt do the crank as it has Peek coated washers and all the bearings are MicroBlue polished and coated.
Done before the Stealth coating was introduced in NZ.

[TZ350]

More com or higher msv , both do exactly as the graph shows.

That must be it.

If comp or squish haven't been changed, could the central plug create a faster & more efficient burn, and be producing higher pressure quicker.

The plug in the original NSR head was offset to one side and very masked. It was a lot of compromises to get the NSR head to fit the short stroke motor. VHM's blank replaceable head inserts were a lot easier to work with. If I wasn't lazy it would have probably been easy enough to make inserts for the NSR head.

Instead of buying an expensive VHM setup if you have the skills, converting a NSR head can give just as good results too.

[Vannik]

TZ that seems a very difficult way - we take a top head, cut off the outlet, weld the hole closed and add the inlet to the side.

[SwePatrick]

I'm searching for a piston with certain dimensions and i figure i search in your knowledge too, it might speed up my process a lot

Demands:

Diam 66.5-67mm
1x piston ring with retainer pin 6 O'clock
18mm wristpin

Compressionheight isn't that very important, but around 38mm would be nice.

Rgds
Patrick

[Flettner]

plugged the LINK in tonight to have a little look at the new (to me) software.

[TZ350]

I'm searching for a piston with certain dimensions.
Diam 66.5-67mm
1x piston ring with retainer pin 6 O'clock
18mm wristpin

https://www.unimotors.ro/Kit-piston-...r_p_68103.html

Take a look at a 1986 Suzuki RM250. 67mm std plus over sizes. 18mm pin, and maybe 6 o'clock ring peg.

[husaberg]

I'm searching for a piston with certain dimensions and i figure i search in your knowledge too, it might speed up my process a lot

Demands:

Diam 66.5-67mm
1x piston ring with retainer pin 6 O'clock
18mm wristpin

Compressionheight isn't that very important, but around 38mm would be nice.

Rgds
Patrick

http://www.mitaka.co.uk/CATALOGUE/PISTON_DIMS_ALL.htm
http://www.tkrj.co.jp/
https://www.pro-x.com/wp-content/upl...019_Online.pdf
http://www.pvlsverige.se/vrm/index/index22.html
http://www.mingyang-group.2u.com.tw/...Motorcycle.pdf
http://www.na.vertexpistons.com/Prod..._details_id=31