Crud!!!

[Surfdancer]

Took apart the top of my ZRX last weekend to do some minor housekeeping :evillaugh:

After 18,300 miles, with a jet kit and Arata exhaust (dyno test showed spot on around 13.2:1 Air/Fuel), I see this :wall:

Time to clean up some crud - it was mostly on the intake valves. Exhaust and head had light carbon soot. Tops of pistons were fairly clean.

Guess I have to start adding Techroline or sumptin' :doh:

[DK]

Might be from a lot of heat built up in motor from being in traffic......

Idles speeds at peak temps......
(13.2 Air to Fuel Ratio is most likely not present at idle speeds)
(Carbs)
(I can't think of any tuners that would be willing to dyno machines at 230 deg F temps either = Idle speed temp of engine in sustained traffic)

Seems to be a lot of wear on the valve stem from friction (heat drag).....

On the exhaust valves it would not surprise me to see oil leaking past the valve guide seals......(just aids lubrication and taunts EPA)

How does the intake side look?

With the amount of carbon build up you may want KWS to do a vacuum test on the valves to see if the seats are pitted.....

See if the combustion chamber is tight/ sealed......

[Surfdancer]

That is the intake...

The exhaust only had a light coating of loose soot.

Piston crowns look good - only light varnish.

Kevin did the dyno run and told me not to change a thing - he complimented the jetting (a modified airbox kit from Ivan's Performance, specifically for the ZRX1200R).

[Mike]

Damn, that's the intake? It looks like one of those Shell this-is-what-happens-when-you-use-cheap-fuel ads. Wow...

[DK]

:lol: (intake)

Dude, take down to champion and have Randy Morgan set it up on the EGA machine to lean out the idle circuit.... (= compromise )

You'll have to drill and tap each head pipe to set fuel mixture screws properly, but it may ultimately lose you the throttle response you are looking for.....

Carbs = Compromise...... Each circuit flows the entire time unless you use electronic power jets or accelerator pumps ....... If you have a great mixture in the throttle position you want than leave it alone......

I have yet to see any dynojet research on setting fuel/air ratio at idle speeds..... It could be done, just have not seen one and many tuners are not concerned with it.....

This is still a "Street Bike".......

Be careful when using fuel system cleaners without nano style fine fuel filter as they clean the fuel tank out also loosening all the rust building up inside.... On a newer machine is not a concern, but on those old beaters everyone wants to bring back to life, the cleaning agents strip the trash from the fuel tank and simply deposit it in the carbs..... Clogging jets or causing the needle valve not to seal up properly dumping raw fuel in the engine if the bike uses gravity fed petcock or the vacuum operated petcock does not work properly ......

Scotch the valves, lap the seats again then have Kevin Hunt Vacuum test your work when finished.....

Then ride the bike another 18,000 miles and play with it again later.......

Or just call Muzzy for some of his round eye Superhappyfastgogo stuff......

The ZRX engine is tough.......

I like them ......

Have fun in there and nice pic.......