Spoke to him today to let him know the coated stuff will be up this week...crank going off for balancing this week...he'll get my care package also...then it just a case of ordering a full spread of bearings, parts etc etc and then rebuild...
Well, everything you see in the pic in the boot of my car was 700 quid. i think the exhausts and all the extra stuff would account for about 150 of that (or thereabouts). On a side note @HYPERBIMDUKE ive got the heads in work with me today to start the tuning....how long did you spend (timewise) on each head....?
On a side note @HYPERBIMDUKE ive got the heads in work with me today to start the tuning....how long did you spend (timewise) on each head....?[/QUOTE] Andy Using decent carbide burrs about 1hr each, I found the tappered xmas tre profile easiest to control, needs 2 hands on extension, i to guide & the other to stop it climbing around in the port. see piccies below. Flat plateau around guide, mine looked worse than yours, but still room for improvement, taper this out all around Ridge from valve guide boss plateau, reduce this to blend with port diameter & reduced guide plateau
So, essentially "make the conical bit" thinner so it still tapers out,...just less of it...ive got all the time in the world so i can spend as long on it as i need to...! Also, polish the lot to a mirror finish? and also the top (around the valves) polish that to a mirror finish too? What were the differences (performance wise) once it was done..? Ah, last of all which type is best the metal Carbide type or the stone ones...?
Well, may as well ive only got this real one chance while its all apart. Been doing some research on the net, lots of nice pictures so i can see the extremes some people go to....ill just go with what im comfortable with....you cant really go wrong....that huge lump of alloy gets in the way of exhaust getting out....the less of it thats there the better its going to be...knife endging the back of it will be the most delicate part. Ive done loads of 2 stroke barrels years ago so i know "the type of work" its just this shape is new to me. Last bike i did was my 7/11 20 years ago and that made a really nice difference. Im assuming that once im done it may need to go back on the dyno to make it really worth while...
Just collected this from the post office...aftermarket gear return spring from the same people that did the ceramic bearing... Again...while it's apart I may as well....
I love it...therapy....the only side effect is cost...the only thing i did to my gixer was to polish out all the exhaust ports to a mirror finish and also the top of the head (where the valves are) the net result on mine was that it used to go straight to 140ish then crawl round to 155 but after the gas flowing it would pull straight to 155 (and smoother with it..) Preparation...if everything is clean and coated then the reassembly it almost a pleasure to do...
Yep, you got it with the conical bit, use carbide burrs, I used these https://www.ebay.co.uk/itm/10Pcs-6m...407976?hash=item2814c8fc68:g:2ssAAOSwBnVW9lA2 Dont mirror polish the port, google rough vs smoothe porting... If you polish the combustion chamber you will reduce volume & compression slightly, best left alone for a stage 1. Performance gains, felt stronger all over but kept on pulling higher up, 8000-9000 whereas it would tail off at 8000, (I'm running std cans on a decat headers no flapper either) Chris
Great - less work to do!! i think ive got everything i need now...just have to wait til tomorrow lunchtime to get to work...thanks @HYPERBIMDUKE Oh - was one pack enough??
Great. I think its just a case of "a bit at a time" as the final shape wont be seen until most/all of the excess has been stripped away...
Little tip with carbide burrs on aluminium: buy a bar of beeswax and load the carbide burr with a little beeswax every few minutes of work. It will reduce any clogging of the burr to a minimum. Aluminium has a tendency to clog burrs rapidly, and this tip really helps. I port a lot of the aircooled VW race engines I build and have found over the years that this method works best for me. Have fun! Matt