Blaster nightmare keihin carb

[Paul Gentry]

Hey my name is paul gentry i am having a hell of a time trying to get my blaster running and tuned right here is what it has and what it is doing before i had to rebuild it was running rich would not reach full wot any it blew up looked to me like excesive heat from being lean but the thing is cleary running rich any i rebuilt my top end the quad has a dg silencer a kiehin carb with 160 main jet and a k&n filter with no air box lid and that is how it was set up when i got it the oval silences also had no packing or core in it it also has v forve reeds and such. so here is what i did after it blew. i rebuilt the top end cleaned the carb an air filter, new spark plug installed packing and core into the silencer (brand new from DG) and repaired the rubber exhaust clamp any it started up and ran but still bogged at wot so i shut fuel of with it running and once the bowl was close to empty it would rev up to full wot so jetting was my next step so i have stepped it down all the way from the keihin 160 main to a 130 now it ran better but still no right so i went as far as a 122 main and and now back to a 130 the needle is in the middle slot it seems now to have a slow rolling surge at wot also will not idle and the air screw does not help i cant seem to get it dialed in to where it needs to be compression is spot on spark is strong and the plug seems to be grayish in color if i step up to a 142 jet the plug is darker and wet and it bogs down i am just trying to find some help and info so i can enjoy this quad but at this point any info would help thanks in advance

 

[jbuckster07]

First thing I see is not 1 mention of a leak test so STOP. Leak test the motor. a member on here @Awk08 sells them for a good price. If your motor has a leak all this jetting is for nothing as its wrong from the very beginning.

Second, is your TORS deleted or still intact?

 

[Awk08]

you fail to mention what keihin carb and what size ?
anything larger than a 28mm is a waste of time for the engine mods you have....basically none.
K&N + Lid off, up 2 sizes from stock mikuni 230 main jet, silencer = zero performance or jetting required.

IF......that is a 28mm carb, we may be able to help you, if its any larger and chances are it'll never tune to a stock blaster engine.

my best advice and easiest fix for you is to scrap that keihin carb and buy a used stock 26mm mikuni carb..
you have zero mods that require any larger carb than the stock carb.

 

[Paul Gentry]

i will leak test the bike and the carb worried me from the beginning and the tors is deleted i appreciate the replies i will check into this stuff and get back with you guys tomorrow leak test you are talking a leak down test?(compressed air into the cylinder?) or is it different on the two strokes?

 

[Paul Gentry]

also how do you identify the keihin carbs just off of measure or do they have numbers on the side to identify?

 

[jbuckster07]

i will leak test the bike and the carb worried me from the beginning and the tors is deleted i appreciate the replies i will check into this stuff and get back with you guys tomorrow leak test you are talking a leak down test?(compressed air into the cylinder?) or is it different on the two strokes?

Yes its a leak down test, but different than a car leak test. You need a special tester. There are guides on here to build your own. look in the DIY Section.

 

[Awk08]

are talking a leak down test?(compressed air into the cylinder?) or is it different on the two strokes?

why: http://www.blasterforum.com/threads/about-air-leaks-save-your-engine.55537/

how: http://www.blasterforum.com/threads/leak-down-test-video.57629/

where: http://www.blasterforum.com/threads/leakdown-testers.55015/page-5#post-791943

 

[Larry's Shee]

I see mention of silencer, no mention of which pipe,head pipe, expansion chamber.
Measure inside diameter of engine side of carb.
No !mention of retorque of head/base nuts after heat cycles.
Was this carb on before rebuild, and was useing 160 jet, and was running OK ?