blaster porting

[yamahamotocrosser40]

i have a 04 blaster and i am looking to do either trail or mx porting and was wondering if i do this am i going to have to change the timing and if i do how do i do it?

[369DuneBunny]

you don't have to change the timing. that is personal preference.... but the standard seems to be +4, or +5......

i'm not exactly sure how you do it, i know you have to make another notch for your degree key and spin the flywheel the correct way... but other than that ask someone else.....

advancing your timing gets you off the line quicker, but also takes away from your top end.

guys who drag short distance straights want to get off the line faster, cuz they don't need all the up top that a longer distance race would give them. ..... since you're on a mx track i don't see why you would need a whole lot up top. so advacing your timing +4 is a reasonable thing to do. even if you want more up top because it doesn't take that much away.

i saw your name was motorcrosser. there are alot of ppl who do straight MX port jobs. trails are kind of all around and would most likely work for that too....

eviltwin who owns flotek porting did my work. i am very happy with it.

[yamahamotocrosser40]

if i dont change the timing will it be fine or will it run like crap exactly what does advancing or retarding the timing do

[369DuneBunny]

advancing the timing gets your cylinder to fire sooner. retarding it gets it to fire slower. advancing the timing too much would almost be like pre-ignition/detonation which is a bad thing. it's important to run the right octane fuel doing stuff like that.

[Ed Gein]

There are also adjustable stator plates for Blasters......running a higher octane fuel comes more into play when you up your compression, more so than a timing advance......

[yamahamotocrosser40]

would 93 octane pump gas work with a ported 240 big bore, and it is not necissary to change the timing

[369DuneBunny]

timing changes would be recommended. as would higher octane fuel cuz you're gonna want to get a head cut to match your portwork.

[369DuneBunny]

fuel just depends on what kind of compression you have. you won't know until after the bike is built. you can always have your builder guesstimate for you... if you can't run pump gas i would recommend AV 100LL fuel. it's cheaper than race fuel and the octane fluctuates higher than 100. elevation and jetting can make it about 126 octane.