Just finished a lengthy google search session for any information regarding fueling a 351, 330, 331... No charts found.. A good bit of piehole spew about using a DJ132 - no doubt because that's the largest jet in the kits.. We have the most information available regarding this subject, and we still lack charts to prove a fueling setup with a performance modded BB KLX..

As far as I can tell, BB KLX fueling is still done with "follow the herd" setups.. No telling how much power is lost doing that..

 

You must have misread my post pretty massively..... in fact i said the exact opposite of what you are insinuating. Do you see where i said I wish there were dozens of them but there arent??May want to go re-read it.

I even said in the post CRF's and BMW's and lately ive seen KTM's etc. Go google "big bore smaller main jet dyno" in google. Information aplenty and there is a LARGE number of people end up going down on jet size, across multiple brands and engine sizes and carbs. People that actually did dyno testing to confirm. Not just theories from people who are guessing what happens (which by the way is exactly what you are doing).

I have an open mind that it may be POSSIBLE that the KLX CVK carb responds the same way, you obviously don't...thats perfectly clear to all of us.... I'm not the one calling dozens of people morons,"piehole spew", or any of the other pejoratives ive seen you use. Thats pretty low class and arrogant.

 

Popcorn-eating emoticon.

 

I'm actually just doing my job.. With decades of "follow the herd" KLX fueling setups, the Dyno developed fueling recipe produced results/power and components that are quite far removed from the "herd mentality" recipes of old. I set out to find out why - I did find out why, as well as becoming knowledgeable of the design and functioning of the CVK34 (and only the CVK34). Therefore, I generally advocate "non standard" thinking when it comes to fueling with a CVK34 whenever "standard thinking" does not "sit well" with me..

You obviously have not "given in" to either side of this issue given that you've decided to "stand pat" with 140/1N lidless after BB. And that's good. So let me do my job with a different tack.

Since there is no Dyno developed fueling recipe available online for BBKLX+lidless+CVK34+Performance Exhaust, we are forced to speculate.

Researching/Googling will produce two camps of thought.
In one camp we have the "Go smaller on the main jet". This is backed up with opinions on how Bernoulli's principle and increased airflow/volume (through any carb) will increase the fuel flow through a main jet. Also, some owners that went smaller and ended up with a "good running" bike. Some say they Dyno'd, but there are no charts posted to back up the claims. You find advocates of this camp easily.

In the other camp is a small smattering of BB manufacturers (Bill Blue etc) as well as a few motorcycle mechanics that build BB's for customers. These peeps actually have to jet BB's for customers and a few take the time to post. They go up on the main jet size. You spend a great deal of time to find these few postings - they are the "needles in the haystack".

Put creditability in whomever you want - we have no data to back up either camp.

I could go into a long boring diatribe about the effects of increased volume and vacuum on our MAJ operation therefore emulsion tube performance, how little extra fuel can be drawn from a main jet that's already operating at max flow, etc etc. But in the end it would just be educated guessing.

 

And that is my point.... I don't call people morons for stating what works for them when i have no data to say either way, that aint right. I don't put 100% credibility in anyones opinion unless they can back it up with dynos/proof, but you also have to be able to "read between the lines" at what people say works especially those claiming dyno use, and there certainly are a lot saying they went down a size or two.

You're right, i havnt "given in" to anyones "camp" except your 250 recipe because you can back it up with data and i have confirmed that it works, its obvious that it works just riding it. Had i been staying 250 I would have done 144/1N. But i feel 140/1N should be "in the ballpark" for where I need to be with a 330 (hopefully), and I will butt dyno/real dyno my way to whatever is optimum. And optimum for me may not be 100% about max RPM HP numbers, I know I would glady give up a hp or two up top if it meant another 5-10 mpg or some additional tq in the range i normally ride because mine is not just a weekend toy.

People selling BB kits also probably err on the side of caution and tell people to jet up, better to be too rich than too lean and blow a piston.

 

Well I know you're reacting to my attitude, and not my words, and that's ok - I can respect that.. But I don't call any person(s) morons - the quote is "yet that is exactly how crap setups and moronic setup ideas become the "norm" online.." no reference to any one person or any one setup idea.. And "piehole spew" is just simply funny, well to me.. Arrogant?.. Well, I've been called worse.. but I'll be the first to admit that I don't know what happens when you fuel a BBKLX using a progression/permutation off DJ144/1N to arrive at DJ146/148/150 @ 1N.. I only know what happens to the power curves of a KLX250 when you feed it correctly and would delight in knowing if a BB responds the same.. Anyone that dyno's such a combo would give proof as we know the typical power output of typical mod lists with 351's..

 

Hey @s10gto what piston did you get? I got a Wossner, but yours looks different....

Also, which way does the 2nd ring go? The FSM says to put the "R" side up, there is no "R" on my new ring, but there is the printed text N200 or something, i have that side up.

All my ring gaps are barely in spec on the tight side, ring tension seems really...really high... but I have not ever installed brand new rings before

Did you put RTV/Silicone on any of the gaskets? FSM says just to put a small dab where the crankcase halves are for the base gasket only.

Thanks

 

I got a JE piston. As for rings, put the N up as you have it. My top ring gap was a little tight. I just had to touch it up with a fine stone.

put RTV on the case halves seams only. Just a dab will do. Also be sure to use a moly paste on the head bolt threads and bolt head under side.

keep us posted.

 

What did you use for your ring gaps? The factory service manual says a .2mm as the min spec and both my rings do meet that spec, but they will not take any larger feeler that I have so they are very close to that min spec.

Wossner recommends .004" times the bore (about 3.25") for NA apllications, which is .013" or .33mm. I'm probably going to call kustom Kraft, on Monday to ask him what he wants, if it goes kaboom at least ill have his blessing

 

And my oil ring fails the FSM max of .7mm.... not that i am using the stock cylinder (or specs) anymore...

My new ring gaps are Top Ring-.200 mm, 2nd Ring-.200 mm, Oil Ring-1.066mm

My old rings are Top Ring .35mm (factory max), 2nd Ring .35mm (factory max) and oil ring is somewhere between .2 and .7 (didnt measure exactly but passes both min and max).