BBK + 4 degree advance

[hotrodaj_2]

Is it ok to do the advance on a BBK. I got a freshly rebuilt BBK and I did the advance. I'm now second guessing myself. What do you guys think? Will it be fine or is that a stock bore thing. I have'nt rode it yet and it can always be changed back. Looking for some opinions on this. Thanks.

 

[99LRDblaster]

Shouldn't matter. The only thing you changed is the bore for the most part. Go run it and see how it runs.

 

[Awk08]

i'd have liked to see you run the bbk without the advance at first, then when you do the advance you have a feel for it, to go by, and be able to tell whats goin on when you advance it

 

[99LRDblaster]

i'd have liked to see you run the bbk without the advance at first, then when you do the advance you have a feel for it, to go by, and be able to tell whats goin on when you advance it

Good point. Probably wouldn't hurt to ride it for a while without the advance and get the jetting in the ballpark first and FULLY broken in, then play with the timing advance.

 

[hotrodaj_2]

i'd have liked to see you run the bbk without the advance at first, then when you do the advance you have a feel for it, to go by, and be able to tell whats goin on when you advance it

Ya, I hear you. This is not a new BBK, It's actually on the last bore now (73mm). Not looking forward to resleeving in near future but it is what it is. I have rode it with the stock timing before. I know the advance will take a little from the top and put it plus a little more on the bottom. I was wondering if the BBK's have enough torque to start with and do not need the advance. I do still need to dial in the jetting (long story).Thanks for any opinions.

 

[99LRDblaster]

Ya, I hear you. This is not a new BBK, It's actually on the last bore now (73mm). Not looking forward to resleeving in near future but it is what it is. I have rode it with the stock timing before. I know the advance will take a little from the top and put it plus a little more on the bottom. I was wondering if the BBK's have enough torque to start with and do not need the advance. I do still need to dial in the jetting (long story).Thanks for any opinions.

http://www.blasterforum.com/engine-...iming-running-larger-carb-dyno-example-37787/

 

[hotrodaj_2]

http://www.blasterforum.com/engine-...iming-running-larger-carb-dyno-example-37787/

Good info. Reps 4 u

 

[hotrodaj_2]

I'm not sure what I was hearing. When I was riding hard I thought I heard some slight pinging. I'm not sure. Do the stock cage with boysen reeds ever make any noise. I heard their is no rev limiter on a blatser, is that right. I was thinking I was bumping the limiter. I think I'm gonna roll the 4 dergree advance out of it and see if I hear a difference. What do u guys think? Can I even be pinging, 165psi on the compression.

 

[99LRDblaster]

I'm not sure what I was hearing. When I was riding hard I thought I heard some slight pinging. I'm not sure. Do the stock cage with boysen reeds ever make any noise. I heard their is no rev limiter on a blatser, is that right. I was thinking I was bumping the limiter. I think I'm gonna roll the 4 dergree advance out of it and see if I hear a difference. What do u guys think? Can I even be pinging, 165psi on the compression.

What gas are you running? 165psi is already borderline for higher octane gas. Putting the +4 on will almost definitely force you to run higher than 93 octane at 165psi. Turn it back and see how it runs. My guess is that you probably won't be able to run a timing advance with 165psi unless you are willing to go to a higher octane fuel above 93.

As a side note, you can hear the reeds. They produce the "ticking" sound you hear from the Blaster, NOT a pinging sound. The ticking comes from the reed petals opening and closing and hitting the cage and reed stops if you have them on. You can hear them on any reed valve engine for the most part if you train your ear to hear them.

 

[hotrodaj_2]

What gas are you running? 165psi is already borderline for higher octane gas. Putting the +4 on will almost definitely force you to run higher than 93 octane at 165psi. Turn it back and see how it runs. My guess is that you probably won't be able to run a timing advance with 165psi unless you are willing to go to a higher octane fuel above 93.

As a side note, you can hear the reeds. They produce the "ticking" sound you hear from the Blaster, NOT a pinging sound. The ticking comes from the reed petals opening and closing and hitting the cage and reed stops if you have them on. You can hear them on any reed valve engine for the most part if you train your ear to hear them.

I was thinking the same about the pinging sound. It was a slight ping or reed noise, I havent owned a blaster long enough to know the diff. in sound yet. I'm gonna roll out the 4 degree advance and I think I'll be fine.

 

[2smoker85]

we all have our opinions on advance, me personally i wont go above 3 and with the bbk u wont need it, to me its more for people who want tlittle extra to get above the others, and when i mean little its about 1hp difference. w/o u will be fine.

 

[Surfrjag]

in my opinion the bbk will get hot and cause problems with a compression over 160 and a timming advance without higher octane. there are many variables that go along with this including jetting, and how hard you ride but to generalize this is what i would go by.