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Downunder wonder
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62 Posts
110 deg seems the standard for 4 valve heads but i know my 5valve are on 107
 

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burnin' up the streets
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8,783 Posts
it all depends on where you want your power to be concentrated.

if you want good all around power go with 105/105.
if you want top end go with 107/103
if you want low end go with 100/102

but you will want to check clearances if you are going to differ from stock 105/105
 

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The One
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582 Posts
Discussion Starter · #4 ·
it all depends on where you want your power to be concentrated.

if you want good all around power go with 105/105.
if you want top end go with 107/103
if you want low end go with 100/102

but you will want to check clearances if you are going to differ from stock 105/105
Let me make sure I have this right 105/105 would be best for all around is that were they are stock?
 

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The One
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582 Posts
Discussion Starter · #6 ·
I drag race and the bike has now low end any ways you thank I sould go for upper end power or leave it at 105/105? Were do you have yours?
 

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burnin' up the streets
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8,783 Posts
right now I'm back at stock settings but my bike makes so much power anyway I don't feel the need to mess with it anymore.

do you use low end when you're racing? I always launch at about 8 or 9 grand so I'm never at lowend.
 

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Smokin Hot R1
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78 Posts
BSR-1 what would u suggest for road racing the top end numbers ? clearance on both of the cams? which # is intake ? thank u
 

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burnin' up the streets
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8,783 Posts
BSR-1 what would u suggest for road racing the top end numbers ? clearance on both of the cams? which # is intake ? thank u
I would guess you'd want either mid 105/105 or top 107/103.
the first # is the intake cam.

I don't understand your question about clearance. valve clearance?
 

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The One
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582 Posts
Discussion Starter · #10 ·
right now I'm back at stock settings but my bike makes so much power anyway I don't feel the need to mess with it anymore.

do you use low end when you're racing? I always launch at about 8 or 9 grand so I'm never at lowend.
I do leave around 8 also and once you get out of first you will always be in upper anyhow. I would like to say that I had alot of power also and I was going to have you do head work put last wed. night my best freind died in a bike wreck (see biker down) and I dont think my wife would like very much if I went and spent that kind of money to make bike faster. So until it cools down I am left with what I can sneek in like spliting head gasket maybe degree cams stacks and take it and get tuned.
 

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Smokin Hot R1
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78 Posts
u had said that u changed yours & then back to stock did u have to change the clearance's ? when i did my 2000 i think it was 100 / 102 & shim to the fat side of the tolerance . was just curious what u had done or would suggest just looking at all improvements that can be made to bike for the spring time / racing gasket / head porting / would i have to purchase new sprokets or machine stock one's / or just buy racing cam's 1700.00 or so? your imput is appreciated thank u in adance
 

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burnin' up the streets
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8,783 Posts
I do leave around 8 also and once you get out of first you will always be in upper anyhow. I would like to say that I had alot of power also and I was going to have you do head work put last wed. night my best freind died in a bike wreck (see biker down) and I dont think my wife would like very much if I went and spent that kind of money to make bike faster. So until it cools down I am left with what I can sneek in like spliting head gasket maybe degree cams stacks and take it and get tuned.
gotcha, sorry about your friend.
 

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burnin' up the streets
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8,783 Posts
u had said that u changed yours & then back to stock did u have to change the clearance's ? when i did my 2000 i think it was 100 / 102 & shim to the fat side of the tolerance . was just curious what u had done
I was experimenting with a lot of different things so I could learn for myself what works & what doesn't instead of going by just what I hear.
at one point I wasn't making the power I thought I should so I changed back to stock so I could take cam timing out of the equation.
since that time I've also gone -1+2 so that along with the 167HP & I've been pretty happy to just leave well enough alone.
actually I want to pull my motor one more time (that'll make 7 times I've had it apart in the last year) & put on my latest creation but I need some money to get a valve job & mill.
 

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Smokin Hot R1
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78 Posts
I could tell u where playing with it but that's cazy 6 times in one year i'm like 1 time for each bike I own here's a funny what do u torque your rear sprocket to lol

RIP biker down
 

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burnin' up the streets
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8,783 Posts
I could tell u where playing with it but that's cazy 6 times in one year i'm like 1 time for each bike I own here's a funny what do u torque your rear sprocket to lol

RIP biker down
I think it's 27ftlbs?
I know it's wrong in the manual, I think it says 72lbs.

I just make them good & tight (that's an official term isn't it?).
 

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Drop a gear and Disappear!
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1,922 Posts
how much top end power would you gain by going to 107/103
 

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burnin' up the streets
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8,783 Posts
how much top end power would you gain by going to 107/103
I've done quite a bit of testing but I don't have a dyno so I haven't tested everything/every combination.
in general it will put more power at the top & take it away from the bottom.

you could ask chuck graves I'm sure he know a lot more than I do.
as a matter of fact he is who gave me the sugessted #'s for low end power.
 
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