B12 Skimmed and flowed dot head

[banditdan123]

Hi there. Would anybody happen to be using bst38ss carbs on b12 motor with skimmed and flowed dot head? If so could you tell me what size pilot jets you are using please??? 

[MeanBean49]

I wouldnt want to be using a skimmed dot head on a bandit lump at all. Valves are almost too close before skimming. Better off just porting a bandit head

[banditdan123]

Thanks for the reply. It's got the dot head cams as well. It's been no problems for the past 2 years. Just have a little issue with the fueling under 4K revs. 

[MeanBean49]

Fueling under 4k is normally needles want raising or lowering a bit. Try a washer either way and see if it improves. Then try a whole clip. Pilots and mixture shouldnt make a lot of difference

[Fula28]

We ran b12. With skimmed dot head bst38,s gsxr 1000 serpent micron headers , 150mains std needles, one clip up from lowest point, (rich)  Was rich on Dyno made 149bhp, After jet change 145mains  made 147bhp, lovely power curve, 

[banditdan123]

I've got 147.5 main jets standard needles on second clip down but I've only got a cheap set of aftermarket headers. I'm using dyna 2000 ignition with ignition advancer dyna coils and leads. Got 137 rwhp and 84lb of torque. The headers you had on yours were for a gsxr 1000? 

[boilerdude]

yes. They can be heated and spread apart to fit oil cooled motors.

[banditdan123]

Are they any good for power increase? It's hard to find a decent set of headers for the b12 

[dupersunc]

1 hour ago, Fula28 said:

We ran b12. With skimmed dot head bst38,s gsxr 1000 serpent micron headers , 150mains std needles, one clip up from lowest point, (rich)  Was rich on Dyno made 149bhp, After jet change 145mains  made 147bhp, lovely power curve, 

How much did you take off the head, and what cr did you end up with?   

I'm currently putting together  an 1157 bandit lump, with a dot head, 6 speed box and bst38s.  I've ended up removing quite a bit off material from the combustion chambers to unshroud the valves, but I'm now considering skimming the head to make the compression ratio less ghey.  I've some Kent suz2 cams to fit too. I'm thinking a carful bit of dummy building might be in order.

[banditdan123]

1 hour ago, Fula28 said:

We ran b12. With skimmed dot head bst38,s gsxr 1000 serpent micron headers , 150mains std needles, one clip up from lowest point, (rich)  Was rich on Dyno made 149bhp, After jet change 145mains  made 147bhp, lovely power curve, 

Did you have any issues with the wider serpent headers hitting the bandit frame tubes? 

[boilerdude]

55 minutes ago, banditdan123 said:

Are they any good for power increase? It's hard to find a decent set of headers for the b12 

I believe they offer both better flow and lighter weight. The midpipe fits OVER the joint where it meets with the collector. Like god intended. Not INTO the collector causing this huge backwards turbulence causing lip like the stock bandit setup. 

[bluedog59]

Any idea what model pipes you need please ?

[robbo_64]

Think we're talking about 2 different things here, people have fitted the standard GSXR 1000 K1/2 titanium headers (by heating and spreading like boilerdude said and got decent gains, not sure how much better the Micron Serpent headers would be? Good thing is that the standard GSXR headers are pretty cheap on eblag.  I got a set for £30 posted, although not fitted as yet.

Edited May 25, 2017 by robbo_64

[boilerdude]

2001 - 2004. k1-k4 I believe.

[Madb]

carefull which ones you get. thinking the k3-k4 have a balance pipe welded between 2-3 headers. check before buying them to make sure.

[boilerdude]

whoops

[Madb]

oh well, never mind. hope they are titanium.

[boilerdude]

oh not to worry. I havent ordered any. I have a set of bandit 1200 yosh headers awaiting mountment.

[Madb]

yoshi is all ways good,eh.

[boilerdude]

My most recent brainstorm is to try to consolidate my collection over the next few months and start with a low mileage bandit for a stock piston, ported dot head, bst38ss sleeper build. I have these carbs dialed in after much poffering about and getting wrong in every way first. on my well hammered 40k mile bandit. And it pulls very nicely. I cant wait to up the ante just a bit and match up the porting to the bigger intake boots and using dot head and j/k cams on beautiful reliable factory suzuki cylinder bores and pistons (barring 2001 models). Old suzuki's really are the best.

[Fula28]

Ok folks, we used gsxr 1000 micron serpent headers pulled about to suit, no balance pipes or joiners just 4-1 with 60mm slipon can. I know it's not best lines for headers but with out  them on tuned motor it's bloody pointless, You need good headers, at least 38-40mm I.d to make use of the gasflowed head,  Made 0.025" skim on my  dot head  from Memory 12.4:1  comp no pinking or knocking stock plugs stock j,k cams.Stock cdi but green dynas.

Edited May 27, 2017 by Fula28

[boilerdude]

Sorry we may have covered this in another thread but what did you have to do to get the carbs to fit the frame/tank?