F1 Cams

Yesterday I put the 182 mains in and also the Dynojet adjustable needles I bought a few years back and also the thinner air filter I made.I really hate pulling the CV side and bladder out,its a real pain to put back right and not damage the little rubber loop bit.I set the needle to be fully down or at its leanest.A quick spin around the block proved that wouldn't work.It now had a big miss just off idle,to I raised the needle 3 from the bottom and did another ride,much better.Its a absolute pleasure when jetting to get a definite effect from a change.I spent a long time playing with jetting trying to fix a cam timing issue a few year back.That's why I had the Dynojet kit,its designed for a Honda CB1000 Big,that's what the carbs are off and I am now happy I bought the kits.So today I did a 120k lap of The Old Rd as an test,It was a peach of a day up there.What with the footy final on,Double Demerits applying for the long weekend I was almost alone up there.On the road the bike performed very well,its hard to tell how the main jet change works,it still pulls like a train.The only problem I can feel is with the leaner setting of the Dynojet needle it seems slightly weaker pull just off idle.It still lugs well,just not as well as before with the std needle shimmed up with 2 washers.Time for another dyno run I think,problem is its going to have to be another Dyno as the one I have been using  has been sold and its replacement is a month off,to late for me to prepare for The Snowy Run.At least I will confirm the AF ratio.
 
Tried a few more needle clip positions on the Dynojet needles.Earlier I had tried the top notch or leanest position.Big flat spot,so I had gone to 3 from the bottom.That was better but not as good as the std needle with 2 washers under it.Today I went full rich and again lumpy and not as good as the std needle with 2 washers.Other than smooth power off idle I am trying to eliminate some annoying popping on the overrun just above idle.Applying choke removes this but the dyno operator tells me the std needle 2 washers is rich,bit of a dichotomy.So as an experiment I put the standard needles back and wack another washer in,that makes 3 and do another test ride.Power is back to the best its been,creamy smooth with the ability to lug away from 2k.The popping is better but still there.So I dialled in 1/4 of a turn out on the idle screw and I am thinking thats as good as I can get it.I will snug up the exhaust a bit and do a longer test tomorrow.Back to the Dyno soon for confirmation.
 
Vince, check the carb to inlet stub connections, any vacuum pipe connections and any other pipework around the carbs. It could be sucking air in from that side too.
 
Nothing to unusual about the work jetting carbs.I have a JD jetting kit for the FCR on my Husky.It has 2 triple tapered needles and a chart that corresponds to temperature and altitude,you defiantly can tell if the winter needle is in during summer.These modern carbs  work generally OK but if you are chasing perfection they do respond to fetaling.I went through all the possibility's with the dinojet needles on the CV Kehans but none worked as good as the std needle with 2 washers under them.So I then worked through no washers 1,2and 3 washers and again it was best at 2 washers.I still had the popping on the overrun so I started working through mixture screw setting,it ended up at 3 and 1/4 turns out.Probably should go 1 jet bigger on the idle jet .It now is as crisp as I can get it and no popping.Today I did a run up the Putty Rd with Marty and did a MPG check,its now doing 45 Imperial miles per gal and pulls really smoothly.Defiantly dyno time soon.
 
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