bs34's junk?

I see that this is another thread that has lost its focus and has turned into the usual useless dribble. At this point it no longer belongs in the "Technical" section but in

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. Question asked, and answered. Good by.

anything can be turned into junk if not used for its intended purpose,a set of 38 flatslides is equally junk on a stock kz motor!hows that sound people?
ever tried driving nails with a rubber mallet? a 20lb sledge doesnt fair much better! :woohoo:

hardr0ck68 wrote:

Does it really matter what carb you run? So long as the fuel-air mixture is right through out the rev range and the carbs themselves are not to restrictive.

I cannot see how it matters AT ALL to the cumbuston chamber what style/make/model of carb is feeding it so long as the mixture is right (and stays correct when changing from idle, to low, to mid to WOT, which is a question of tuning so long as the carb in question has no design flaws).

Do the RS carbs have pixie dust in the float bowls that magically help them make more power than BS carbs on the same engine while filling the cylinders with the same fuel air mixture?

Or the BS carbs are flawed in some way and cannot give a clean f/a mixture at all throttle positions?

You're sort of on the right track here - right school of though, but there are differences in how the fuel is delivered and the control at which the rate of more or less fuel is delivered.

A carb that is twisted say wide open from idle (with load) doesnt just deliver a fixed amount of air/fuel because its wide open. It delivers based on the demand of the engine. Starting out with a more fuel rich ratio, that tapers out to a leaner ratio at high rpm.
All with the throttle held wide open.

Sounds rediculous, I know. The jets dont change, but the air speed does, and the engine burns more efficiently at higher rpm, thus going leaner as the engine accellerates... puzzling - I KNOW :laugh:

OK, so we all know how CV and slide carbs are different. CV uses vacuum to lift the slide, and regular carbs, the slide is lifted via the throttle control.

Those two differences aside, both carbs can deliver excellent performance on both street and strip, however, because of the way the carb delivers the fuel over the range of engine demand/vacuum is different, and the difference generally shows in the way that the slide carbs tend to maintain a more rich, linear delivery of the fuel across the demand of the engine, closer to what an engine needs to make torque. The cv carbs tend to be more finicky (especially when tuning), and "seem" to lean out sooner based on the engine demand.

ALL OF THIS can be compensated for, depending on the performance you want out of the carb.
But... its give and take with both, just depends on your tuning skills - and carb size... and fuel used... and compression/engine configuration... and...

I have both types. I enjoy both, highly tuned. They both respond instantly, and give excellent results. They just feel different, and have more power @ different speeds and situations.

So to answer your first question, NO. It doesnt matter which carb you run. It can be ported, polished, jetted, rebuilt, whatever to be better at "something", than the other.

It is VERY, VERY hard to tune a carb perfect for engine demand. Really its (dare I say) impossible, which is why we have fuel injection, like on the NEW bikes which is now "on the fly" open loop F.I. which can change the fuel input based on engine demand and a slew of other factors which make for alot more power in all different situations.

:woohoo: breath!

This is why true jetting can only be done by experienced feel, or a dyno. Unless you run the bike at one single rpm, at one throttle opening for long periods, than forget about jetting by your plugs!

nads.com wrote:

I'll render my opinion of her.
After I smell your finger.

This is my GPz1150 with .420 lift cams and ported head. she moves like a bat-auta-hell. Will the BS34s compare to the top notch smooth-bores for drag strip use? NO. But they are one of the best street carbs around.

otakar wrote:

I see that this is another thread that has lost its focus and has turned into the usual useless dribble. At this point it no longer belongs in the "Technical" section but in

---

. Question asked, and answered. Good by.

If you READ that last line of the "original Post, you see that this thread starts out as "Dribble"...

Nads knows how to word his postings to "Insight Dribble"

Than we have more Dribble about "Scratch Built" GPz1150's.... Here's the Quote. otakar wrote:

I run a set of the Mikuni BS34s on my Built GPz1150 with .420 cams and oversize valves and flowed head and I will put my bike up against anything that runs smooth-bores on the street.

"None of You Can Handle The Mid-Range Truth"

Much like you couldn't handle the Dupli-Color Truth

hardr0ck68 wrote:

Does it really matter what carb you run? So long as the fuel-air mixture is right through out the rev range and the carbs themselves are not to restrictive.

I cannot see how it matters AT ALL to the cumbuston chamber what style/make/model of carb is feeding it so long as the mixture is right (and stays correct when changing from idle, to low, to mid to WOT, which is a question of tuning so long as the carb in question has no design flaws).

Do the RS carbs have pixie dust in the float bowls that magically help them make more power than BS carbs on the same engine while filling the cylinders with the same fuel air mixture?

Or the BS carbs are flawed in some way and cannot give a clean f/a mixture at all throttle positions?[/quote
I'm thinking flatslides will generate a potent mix for my air stream. If I have one that is I pulled of a stop and a gs (nice) was next to me , he took off easy but it had mid punch you could tell. I never gave much throttle but His mix was crispier. It's nice to have that to get me going ya know. Then when I hammmer it I should be impressed as one can get. Unless I ruined the head :woohoo: but that's not gonna happen? I think I know what I'm doing here pretty well. I'm gonna use long lobe centers and see what I can get for output, minor valve timing changes will be made once I'm over the carbs new power. I know where I want that power and how and when,, I've got the bike dialed at all speeds and gears for instant redline in whatever gear. Need to open this rock box up somehow that's all I'm doing. I'll be out pressure washing and blasting everthing then starting essembly all together this week. After I finish the head monday or tuesday. I don't like seeing my bike all over the place it's worth nothing to anyone that way, so that's my incentive. Plus I'm anxious to see what this thing can do. The head flow. Larry ain't scared of no top secret head. This will be the real deal. To a good extent, has to be, or I'm THAT dumb! NO way?

How many sets do you want...? :blink:

Old Man Rock wrote:

How many sets do you want...? :blink:

Quick!!!! Buy them before the US Navy spots this post :woohoo:

Do the RS carbs have pixie dust in the float bowls that magically help them make more power than BS carbs on the same engine while filling the cylinders with the same fuel air mixture?

Or the BS carbs are flawed in some way and cannot give a clean f/a mixture at all throttle positions?[/quote
I'm thinking flatslides will generate a potent mix for my air stream. If I have one that is I pulled of a stop and a gs (nice) was next to me , he took off easy but it had mid punch you could tell. I never gave much throttle but His mix was crispier. It's nice to have that to get me going ya know. Then when I hammmer it I should be impressed as one can get. Unless I ruined the head :woohoo: but that's not gonna happen? I think I know what I'm doing here pretty well. I'm gonna use long lobe centers and see what I can get for output, minor valve timing changes will be made once I'm over the carbs new power. I know where I want that power and how and when,, I've got the bike dialed at all speeds and gears for instant redline in whatever gear. Need to open this rock box up somehow that's all I'm doing. I'll be out pressure washing and blasting everthing then starting essembly all together this week. After I finish the head monday or tuesday. I don't like seeing my bike all over the place it's worth nothing to anyone that way, so that's my incentive. Plus I'm anxious to see what this thing can do. The head flow. Larry ain't scared of no top secret head. This will be the real deal. To a good extent, has to be, or I'm THAT dumb! NO way?

hmmmmmm..... Let me see how to explain this so you get it.

If the lobes are long you can't go wrong,
If the bike's a gem you want a VM
If you want the best use CRS
If the bike's a racer use RS with a spacer
If you're being selective, just go injected :laugh:

BS34's Rock if if you race without a clock
If you twist the wrist, don't expect any bliss
To cure the 5K stumble... lift the needle and grumble

If someone told me earlier there was a difference between synch and sink... I might not have used BS34's for a boat anchor :woohoo:

Having exhausted his supply of jet needles to tune his BS34's for the big block motor.... Little Plum heads to Walmart for some finishing nails to modify into carb needles.... I was there and I saw it with my own two eyes.

hoghaterkaw wrote:

Anyone who wants a seriously fast street bike isn't going to waste time on a thirty year old bike if he is indeed serious about speed.

:woohoo:

It's about hard core acceleration HH and guys are still doing it. You're right about the proper application for BS34 carbs but you're dead wrong about this one I'm afraid...


It's still one heck of a thrill to go 0 - 120 just as blistering fast as you can and it' doen'st take a 2011 model motorcycle to provide that thrill either.

Hell... you had a GS1100. You know how that bike pulled in the midrange. Dam impressive wasn't it But, have you ever thrown a leg over one that with a done up head, some Yosh Stage 1 cams and a rack of VM33 smoothbores? If you ever do, I hope it's nice sunny day because you'll get aq good look at the sky and feel like you no longer need Viagra :woohoo:

Good point Lar...

Larry, Plumi and I have discussed something that hit me like a bolt of lightning when designing/building my engine... Based on the cycle mags depicting new bikes w/ Dyno recordings and comparing to my build...

Almost identical recordings in the curves up to 100mph @ 8-9Krpm, these 30 year old KZ's with some minor mods (displacements, head valve P&P, Carbs, gearing,l exhaust etc...) are pretty much the same in torque and horsepower ranges...

Now before everyone get's there panties in a bind, sure, depends on the bike style such as MVAgusta, Bimota, Cagiva, Yamaha R1, Ducati and the new BMW 1000 (Drool) just to name a few... Meaning the 188mph out the door $30k - $80K GP bikes....

If you look closely at their curves up to 8Krpm... not a whole hell of a lot of difference in most cases...

Sure, Once they hit the 120mph mark, rev limiters and 4 valves kick in no way we're going to meet that on a street ride...

But as Larry just pointed out, up to that point, pending our KZ builds & gearing... we're even faster in the butt puckering acceleration factors in some cases...

My bud on his interceptor still flips me the bird when I 5th gear twist the ole girl on him... Down shift and twist her hard... He really gets pissed off as I shake my head & wave bye-bye.....

Or as Big Sid says "Ya got it all on?" and pulls away."Big Sids Vincati"-great book.bj

hocbj23 wrote:

Or as Big Sid says "Ya got it all on?" and pulls away."Big Sids Vincati"-great book.bj

i thought were talking about my hero Sid Pogue! :laugh: