the 04 blaster we have that keeps blowing up has a Toomey b1, weve played with jet sizes an still does. im bout to put it together again and Toomey said it takes a 310 main and stock pilot, my dealer thinks I should change the pilot too but Toomey said no. so should I change it or leave it stock and just try the 310?
main/pilot jet
- Thread starter Reaper26
- Start date
Leave the pilot stock 32.5 stock.
At sea level, this may help.
TOOMEY #310 main jet.
Aftermarket air cleaner + 1 or 2 size larger.
Air box lid off +2
32:1 pre mix +1
Needle in the middle slot.
32.5 pilot jet
Plug chop to confirm, as temperature, elevation and humidity come into the equasion
At sea level, this may help.
TOOMEY #310 main jet.
Aftermarket air cleaner + 1 or 2 size larger.
Air box lid off +2
32:1 pre mix +1
Needle in the middle slot.
32.5 pilot jet
Plug chop to confirm, as temperature, elevation and humidity come into the equasion
coreect piston to bore measured, bored/honed and fitted each time ?
was it leakdown tested ?
new head/base gaskets every time ?
heat cycled and head/base nuts retorqued after final heat cycle/cool down ?
32.5 pilot and airscrew adjusted correctly ?
stock needle w/ clip in middle slot position ?
main jet plug chops ?
nobody, not on here, not your local mechaninc, not Toomey, or even any NASA engineers can tell you what main jet any bike or any mod requires, only plug chops can confirm main jetting
was it leakdown tested ?
new head/base gaskets every time ?
heat cycled and head/base nuts retorqued after final heat cycle/cool down ?
32.5 pilot and airscrew adjusted correctly ?
stock needle w/ clip in middle slot position ?
main jet plug chops ?
nobody, not on here, not your local mechaninc, not Toomey, or even any NASA engineers can tell you what main jet any bike or any mod requires, only plug chops can confirm main jetting
Are you using good oil? and are you sure your oil pump is getting oil to the carb? bleeding oil line? Also what do you mean by blowing up? Melting pistons? snagging rings? broken skirt? etc etc.. Some pictures would help us to as what direction to look into , as well as a description of your definition of "blowing up".. the more details the better..
yes to all above, i only use yamalube in my blasters and banshee. it broke the skirt twice, and the last time the piston melted, we used a namura that time, trying to see if they were any good. i always bleed the lines after building, and its pumping great. it has both new cases, new seals, bearings, crank, its basically a new engine. the main we had in it this time was too small, it was a 280, had a 350 in before that. its had problems like this since we put the toomey kit on it. the only one ive ever had a problem with, i ran mine with just a set of reeds, spacer, wiseco .20 over pro lite for 2 years with a 360 main and it ran great, until it got stole, when i found it the dumba$$s filled the oil tank with engine oil and completely melted the piston to the rod, i had to cut it off, i didnt have a new piston or the money to buy one cuz the shee was stolen too and i built it back first, i had a used stock piston and cylinder that i put back in and its ran good for 3 years, im building both of them friday though when the new pistons get here.
Are you having the bore measured exactly by a professional to see if the piston(s) your fitting have the correct tolerances spec'd by each different piston manufacturer, and/or boring/honing to each specific piston ?
Or just slapping pistons into unknown condition cylinder bores ?
Or just slapping pistons into unknown condition cylinder bores ?
the last time i took it to the yamaha shop an let them send it to their shop they use to bore it, it came back with the measurments on the piston and the cylinder, that was the namura. i usually go to a automotive machine shop, the guy knows his stuff, has always done a good job and he gets them back really fast, usually a day. the other place kept it a week.
What did he set the measurements too ? A bad hone job or off center re- bore can piston failure. However most often piston skirts braking off are due to improper piston to cylinder clearance. The stock Yamaha piston will break too, if left in too long. I don't know how good the Namura pistons are ,but they are cheap , I say buy a good forged Wiseco instead. I also don't judge a shop on how fast they get work back to me. If it takes a week then I know they did not rush the job and make mistakes.
Just read the B1 fitting instructions and they did say 3/4 of a turn for the air screw, I would be starting at 1 1/2 turns.
I too was also confused by them saying fit the #310 main jet supplied with kit and then further down the page they tell to take off the air box lid and fit the new air filter supplied with the kit, so maybe you may get away with a #290 main jet, but whatever you do plug chop to confirm.
I too was also confused by them saying fit the #310 main jet supplied with kit and then further down the page they tell to take off the air box lid and fit the new air filter supplied with the kit, so maybe you may get away with a #290 main jet, but whatever you do plug chop to confirm.
Broken piston skirts = excessive piston clearance. Send that chit to CT. I'll be glad to post my findings.
