TZR125 4DL
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Dyno setback

TZR125 Track Dyno

Had a small setback today, weather was good and the new jets came in this week for the 34mm Dellorto.
The Ordered Zeeltronick did not arrived jet, so took the one already mounted on my roadgoing bike (it was plug and play)
Put the original key back for the flywheel so stock ignition is working like a stock ignition (checked the base advance with a timing light)
All was good.

Made a small study of the new carb, quickly realized that the emulsion tube wasn't a bleeding type.
34mm on the Left (no bleeding type)
32mm on the Right (bleeding type, seen with a small jet)
This explains the somewhat rich settings on my first setup (first setup 34mm Dellorto)
I needed to go down on the mains.

Went from a 145Main to a 135Main, engine felt good

First results was the Ignition set on stock timing that gave around 23HP and then ignition set on max advance gave around 27HP (max advance is turning the baseplate to max point about 5 degrees more)

Here you see the jetting 168, 155, 145, 134, Mains
Du to the leaner setup you see the rpm rise

Then I Mounted the Zeeltronick (checked the base advance with timing light, all good)
After one small run (warming up) came the first stored run for the Zeel but the engine broke down on that dyno run.
The run I did measure so here it is. (stock oem curve was set)

I could not feel it Cumming, it was a thheeeelp sound and that was it.
EGT was not showing any problem
Result a seized piston
Before I go further need to investigate the problem, but let me first say
this has nothing to do with the Zeeltronick. (before people make conclusions to soon)

A good thing is that these inline sleeves are strong compared with the 3MA nikasil plating
They can handle these thinks

The head

Piston is having a seizure on four sides
Here the exhaust side

Here the intake side

Head piston

Plug damage

Will investigate what went wrong, as there a quit a few variables

After consulting the forum, I can conclude the problem lies at two main problems

1) The oil feed connection ''diameter'' on the new carb. (its half the size as the oem Yamaha carb)
2) The lean setup (carb was set way to lean, seen in the overrev)

Just wanted to do think to fast.................................

Update: 09-04-2018

Cleaned the cylinder, and it came out well

The tolerance off the piston could be a discussion point.
But it was set on specifications

New piston came in today

V-force 4

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