kingsley

DDU sounds a bit dirty to me. Il have a chat with him, he is about 2500Miles from me but might have some usefull contacts. In the mean time i have been able to speak to a workshop in Melbourne who knows these bores and is confident to weld the damaged section, replate it and supply a piston for around the $500AU mark. Seems like a no brainer to me. One last question...... Can someone recomend a supplier who can supply one 22cc coolhead dome to suit the blaster piston? The other side is still fine. Thanks guys!

Hi everyone, I managed to bust a ring on my left piston and its put nice groove down the side of the Serval bore. The right side is still like new and the bores have done very little work. Can i just repair the bore and recoat back to standard (421cc) on that side or would i be better off boring out the damage on both sides and go over size. At this stage im up for atleast one piston and dome. I have a 7mm crank still in the box so am i better off just buying a new 7mm Serval with pistons and domes? P.s im in Australia so any repair would have to include shipping back to the states.

Is there enough meat in the water gallorys to drill and tap a temp sender or even case a spot there for future barrels? IS this a good place to put it apart from the top hose with a joiner fitting?

Hi Calvin. I believe the question i have asked here is directly related to the time that you spent on Friday for a 7mm crank in a 4mm serval. My reason for asking the question was to gain more of an understanding of the outcome of this combination. I am reasonably new to the performance workings of a 2 stroke. After looking at your PDF file. I notice the exhaust timing is practically exactly the same as the 4mm with 186.3 but the main transfer (inlet ports?) open fully at 3deg later. Again not knowing much on this subject. How different will the result be? My guess is that the torque will be slightly later in the RPM. Is the difference in torque delivery mostly noticed when the inlets are adjusted or when the exhaust is adjusted? Obviously this combination will be different to a 4mm set up as the torque and HP will change again because of the 7mm stroke and i may not even notice a difference or see more. At the end of the day, i came from a poor designed 66.5mm bore with a 4mm crank and running 22cc banshee domes with blaster pistons. The combination was all wrong but i was very happy with performance i had.

If you were to take a 4mm serval,run the 7mm crank, no base gasket and cut domes, Would that be what you would work with? If im right, does this efectivly raise the ports on the serval and increase the RPM level when the torque comes in or does it over come the issue with the extra 3mm on the stroke? Reason for asking is that i will be running that combination with 34mm carbys, +4timing and FMF fattys with 22cc domes. Just awaiting the cut domes.

Are the ones that M&M sell pretty good, i see they have a SS shaft? Are they a strait fit up?

Will the cooling system have to be upgraded when building this engine? e.g water pump and radiator?

Currently i have both air cleaner styles and im running the pods on a pair of 34m carbies. I dont like the idea of the pods sitting out in the open for fear of water, extra exposure to dirt and damage. What has the better air flow? Pods or the single K&N in the air box? I imagine the pods do but will i notice it verses single K&N? Dune/trail use.

Thanks for that. I bought it through Andy at M&M. I only have FMF fattys to start with.

Ive ordered a Serval engine package and it includes cool head domes. Ive also added an adjustable timing plate to it. This will be run with the 4mm crank. When making the order, i stated my fuel will be 93mon (98RON AUS) and run at close to sea level. Ive worked out that id should get 21cc domes thrown my way. Would my thoughts be fairly close or what would i expect to see? Kingsley

How well will the FMF Fattys work on this motor? Dirtydownunder.... How much tax did they slug you?