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Re: jet200 o-tuning à la mode fastfrog
Posted: Tue Mar 25, 2014 9:32 pm
by fastfrog
mag flange greased and refitted.
Tried my new cnc head and got a strange (but classical)issue: I have a negative squish angle... Glurp! needs a reshaping for sure!! I mailed Mark B to warn him about this prob...

Re: jet200 o-tuning à la mode fastfrog
Posted: Wed Mar 26, 2014 9:58 am
by fastfrog
did a slight reshaping and tried without success to move up the head to get a better shape match as proposed by Mark B. Unfortunatly I had almost no play at all... So took my moviluty in my left hand and slowly restaure a more convenient angle (I hope so!). Now Ive got 1mm at the outskirt of the piston crown and 1,08mm just before chamber begins... Sounds fine to me....
Re: jet200 o-tuning à la mode fastfrog
Posted: Wed Mar 26, 2014 2:34 pm
by rondord
Did Mark say you had done something wrong as I'm sure he never makes mistakes.
Re: jet200 o-tuning à la mode fastfrog
Posted: Wed Mar 26, 2014 10:59 pm
by fastfrog
Mark told me to check if head was well centered and propose me to move it up as possible (studs leave a free play of 1-2 mm) to see if squish became more coherent. In my case no real play avalable as my piston heading out 0,5mm of the barrel it therefore centers the head..
Mark doesn't make no mistake but as a froggy I could have described my will in an unaccurate english or forgot a data.... Anyway head has a rather better profil by now and fits nicely upon the piston...

Re: jet200 o-tuning à la mode fastfrog
Posted: Wed Mar 26, 2014 11:51 pm
by dapper
You appear to have a very steady hand judging by the quality of your porting. Very precise. What equipment do you use? How long have you been doing this and any tips for us less experienced?
Re: jet200 o-tuning à la mode fastfrog
Posted: Thu Mar 27, 2014 9:46 am
by fastfrog
moviluty flexxi classic/ 450W pedal controlled. A hit! small, flexible and lots of torque even at very low revs... I've been porting and cutting since I was a teenager. I can clearly remember my first attempts on a solex barrel. I'm now almost 44... "slow lefthand fastfrog" unfortunately I dont play guitar!
My secret is to cut rather slowly and avoid too deep cutting at each pass. That's why I'm using a very torkey engine at low revs. Classical carbide cutters, no stone.
Re: jet200 o-tuning à la mode fastfrog
Posted: Fri Mar 28, 2014 10:00 am
by fastfrog
I'm thinking of an airbox tuning too. I have a serveta lince air box type One 3rd of the toolbox is occupied by the air system. A crappy restrictive sh.t.... But it calms down air flow before going into the air bellow. Like to keep this idea.
My idea is to take the toolbox room to put a real air filter and make in the 2nd chamber sort of a tuned box... Hope I'm clear enough....
restrictor's out:
where I want to weld a tube of a certain length (to be calculated: 4-6cm??). Front hole will be obturated.
Filter in place:

Re: jet200 o-tuning à la mode fastfrog
Posted: Fri Mar 28, 2014 10:36 am
by coaster
Are you going to improve airflow in through the tool box louvres as well FF?
Re: jet200 o-tuning à la mode fastfrog
Posted: Fri Mar 28, 2014 2:28 pm
by fastfrog
coaster wrote:Are you going to improve airflow in through the tool box louvres as well FF?
yes i'll cut them wider...
Re: jet200 o-tuning à la mode fastfrog
Posted: Wed Apr 02, 2014 7:33 am
by fastfrog
S-box ordered.
Meanwhile i've modified the maghouse outter lip knowing a lightened af flywheel is fitted.
