Hello everyone. I bought a decked out blaster for my wife. Complete new rebuild receipts to match not even a full take ran through it. They slapped a new Keihin 28 carb on it and "didn't have time to tune it" rebuild was done professionally a week ago per receipts. I have a great background in rebuilding banshees. However the current situation is this. It had a 42 pilot, and a 148 main. Started and idled fine. However it was obvious it was running lean. I replaced with a 55 pilot, and 155 main. Idled fine, drove fine until wot in fith and six gears. At wot it quit, I downshift and starts itself and drives fine. Came back and for sh*ts and giggles I put in a 72 pilot and a 170 main. Same issue except at idle one time it reved but that is obviously due to the extreme pilot jet. So out of frustration I did some research and several people stated that they had the same issue and required a 165 main jet and putting the air box lid back on.... The bike didn't come with the air box lid. So should I continue upping the main jet probably will be like a 180-190 at this point or should I just pick up a air box lid. The mods are as follows. Keinin 28 blaster carb. No air box lid. Uni foam filter, FMF turbo core exhaust new .9 over kit. I am stumped. On thing that surprises the hell out of me I did not see any smoke coming out of the exhaust until the 72 pilot was installed. On a banshee they smoke if you are one pilot size over, subtle but still does. As stated before I am new to blasters but qualified to rebuild banshees from the ground up. Thanks for any advice I am dumbfounded.
Blaster Nightmare
- Thread starter Ty_shooter2000
- Start date
What are you running for premix ratio? 32:1? I don't see that motor using any more than a 155/55 combo. There are really not a lot of upgrades done to it engine wise. Have you done a plug chop to confirm? Smoke out the exhaust does nothing to tell you its rich or lean.
Slightly richer than 32:1 since it is break in. I am well aware smoking is not a indication of rich but it perplexes me that it does not smoke at all
Started and idled fine. However it was obvious it was running lean. I replaced with a 55 pilot, and 155 main. Idled fine, drove fine until wot in fith and six gears.
^^^your quoted words... Im lost. You say it idled fine and drove fine but now say you can't get it running. So what I gather is you can rebuild engines, are lost on why it doesn't smoke, Running a richer mixture than 32:1 ( which is a false assumption) and finally got it running to do a plug chop and you say it's lean. Your current jetting is massive for what you are telling us. Go do a leak down test to confirm you have no air leaks before you keep pulling our leg any more.
There is no pulling anyone's leg. As I stated the quad idles and runs fine until Wot in 5 and six gears. There is no smoke nor any exhaust druel. I retorqued all bolts and nuts yesterday discovered one loose bolt on intake boot, one lose nut on cylinder and one extremely loose bolt on head. Retorqued all to 22 ft pounds put in a 55 and 165 jet. The needle clip was also in the second position I moved it to third. Took it for a test drive, Ran perfectly through all gears and throttle positions. Returned picked up some plugs did a plug chop this morning and still lean not due to color but the width of smoke ring it was very thin about 1 width of a pencil led. As stated from another post I found a gentleman had the same issue three years ago threw in a 172 jet and was good to go. I am going to throw in a 172 and do another plug chop this hopefully that puts me in the slightly rich ballpark and good to go. I agree with you 172 does seem large to me but maybe because it is bored .09 over? I do not know. But at 165 main jet and third needle position it is smoothe as silk but according to the plug chop still slightly lean. Don't ask me why mine and another's calls for a 172 main because I don't know. That is what she wants to. E in the slightly rich category. This is a brand new build by a reputable shop and I assume that the head bolts were out of spec because of the break in and heat cycling.
PeaceWell guys after three weeks I got it figured out. I leak tested the bike with my friends smoke leak tested. It pressurizes a engine to any pressure you want. It produces smoke using mineral oil. If there is a leak it not only shows on the gauge it will smoke from where the leak is. Passed with flying colors. So out of frustration I ordered a air box lid slapped it on and it was so rich it wouldn't even run other than at idle. So it was a huge improvement. I slapped in a 42 pilot and a 158 main and she runs slightly rich and perfect the way I like them. So my conclusion is this since the bike was bored to 222 cc and since it was getting too good of airflow it was running lean at wot sixth gear no matter what jet was running. So the easy fix was throwing a air box lid on and was good to go. I assume if I would of run a more restrictive filter that would of worked too. Anyhow it is at first clip position, 42 pilot 158 main and good to go.
My 28mm. PWK summer jetting :
KOR porting and head mod with FMF pipe , Toomey muffler , and no air box lid
155 main
45 pilot
JJH needle on second clip from top
KOR porting and head mod with FMF pipe , Toomey muffler , and no air box lid
155 main
45 pilot
JJH needle on second clip from top