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Discussion Starter #1
Your going to like this. I am altering the rocker arms to give us increase lift. no changing cams. this can be installed and all you have to do is remove the rocker covers and put the new rocker shafts in.
It is way to hard to update 5 or 6 forums, just takes to long. so i have a website where i am posting all the info. check it out. i did all the math this morning and will post it later today.
http://www.thebrainsplace.com/new-projects.html
 

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Discussion Starter #6
update; welding and exhaust

Again another update. just click on the previous link to my website. I have one problem. My stock head pipes are killing my power output. I would like to get a good 2 into 1 exhaust system. does anyone know where i can find any kind of exhaust comparison, shoot out info. Would like to get the most bang for the buck when i get new exhaust. there are a couple 2 into 1 systems out there. which is the best to use. would like the most flow possible. don't want to cork this thing up so the HP figures dont show the full potential of the BRA mod. if my exhaust sucks my power numbers will reflect that and i don't want this to be stifled because i bought a crappy exhaust system. how does the VH pro pipe compare to the other 2:1 systems?

http://www.thebrainsplace.com/
 

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Discussion Starter #8
Questions i cant answer

I wanna know when your gonna post actual gains on the dyno and how much the parts are and when they are ready to ship :)
Hard to say when i can post dyno results. the riding days are getting very limited here in minnesota. its been snowing on and off all week. if you buy the parts brand new they cost $375.00 but i bought used heads off ebay for this experiment for $180.00. the cost of welding and machining will be what i add to the parts cost. thats what i am currently trying to come up with. I have a website update you can check out soon. I am very close to machining the rocker arms.
 

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Discussion Starter #9 (Edited)

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Discussion Starter #10
fairly big update. machining has started.

www.thebrainsplace.com

fairly big update. machining has started.
 

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Discussion Starter #11
Hiccups are out of the way - for the most part

I have been slow with the updates. here is what has been happening with this BRA mod. I have pulled my Stratoliner apart to get one of the rocker arms out. I had missed collecting some info on the rocker arms i had welded up and once they were welded i couldn't get the info. I also had some tooling issues that are now resolved. Since i was so close to machining the push rod cup I took this rocker arm i just pulled out of my Strat and checked everything on our OGP Smart scope at work. Good thing i did. I was off a little on some of the dimensions. when talking rocker arm ratios a little can turn into a lot. I have revised my website with the corrected data. as it turns out the valve lift is much less than my initial data showed. the safe clearance between the valve spring retainer increased quite a bit. at this point there is no concern at all even moving the pushrod cup over 3 mm. This is part of the reason i am slow going thru this. I would rather be safe than sorry. I have attached the new info to this post as well. not sure if it will be readable but i reorganized it so it looks better and makes comparing easier. I'm also being slow because it is so friggin cold out there is no way i am going outside to try and turn frozen manual mill handles. It has been below 0 deg F all week and most of next week. the high temp yesterday was -1 deg F. and it was -6 deg F for most of the day and -18 deg F at night. it is supposed to get up to +2 deg F today so maybe i can hack the heat wave and pump out my 4 rocker arms but i would not count on it. But i might. I want to get this done because i now have my Strat tore a part in the house garage and i don't like letting my sweet heart sit there like that. anyway, getting close if weather would permit it.
 

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Discussion Starter #12
The BRA mod is completed.

The BRA mod is completed. I am scheduling a dyno run for this saturday if i can bet the bike back together by then. check out my website. I have pictures of the finished rocker arms and other stuff. The evil holes i needed to drill in the frame. everything. it's almost all done. just the dyno tune is left to do.

www.thebrainsplace.com

I took the old incorrect valve data sheet out also and replaced it with the correct one. I moved the push rod cup hole over 2 MM (.0787" in)
FYI, there is a car website that has all kinds of calculators and i ran the yam 113 though quite a few of them and it looks like the Yamaha engineers have this engine totally figured out for the optimum everything.
http://www.wallaceracing.com/Calculators.htm
good stuff here for sure.
 

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Discussion Starter #13
all done but the dyno tune. see it run here.

all done but the dyno tune. see it run here. the initial start up. sounds strong.

 

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Discussion Starter #14
Today is the big day.

Today is the big day. I can hardly wait. TheBrain is all wiggly/jiggly with excitement. If this works as well as the BAM kit I will be in heaven. so this test is with my Strat set up like this.
2007 Stratoliner S (the "S" stands for Super duper)
BAM (Brains Air box Mod)
BRA mod (Brains Rocker Arm mod)
V&H 2 in to 1 Pro-Pipe
PCIII USB


I will make sure rear tire is at normal pressure for the test so i am not cheating.
 

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Discussion Starter #15
dyno tune completed, website updated

Well, I updated my website. Not what you are expecting.
www.thebrainsplace.com
 

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Discussion Starter #16
baffle plate removed

well i cut the baffle plate out with a hole saw. boy is it loud. sounds much better though. i think the baffle was plugging it up quite a bit. for people wanting to cut this out with a hole saw, a 1-7/8" dia works perfect. now all i need to do is take it back to the dyno guy to be rechecked. all i know is it sounds much crisper. before it was Blaaam, Blaaam, now its Rumbaaa, rumbaaa, hope those motor noises get you going.
 

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Discussion Starter #17
I've learned a lot.

Well, this is my final update. been a long time coming. first, I still have the BRA mod installed in my Stratoliner. I have 5000 miles on the rocker arms and everything is working just fine. the valve train is quiet and everything works fine. Now with that being said. the BRA mod didnt do anything at all. Thats where my "I learned a lot." came from. I hop up lots of two valve engines and make them fast. They are different from 4 valve heads in a big way. on a 2 valve head the main flow restriction is at the valve. so adding lift to a 2 valve head give you more power. this is not the case with the 113 cid engine with 4 valve heads. because the four valves flow so much more than a 2 valve head the valves are no longer the restriction and the only way to control the air flow thru the head is to make the intake port the proper size so that the intake post is the controlling factor. so adding more lift didnt do anything as the port is maxxed out in regard to the flow that can pass thru it. I wondered why the port on these heads were no bigger than the ports on my small block chevy heads, heck they are a little smaller i think. a big block chevy has rectangle port heads with ports big enough to put your fist in. yet the 113 heads have these small ports. thats because the port controls the flow. if the port was as big as a BBC there would be no intake port velocity and the motor would be dead, doggy. it might work at WOT but that would be it. In a nutshell, the only way to make you bike meaner is if you change cams to get more duration or port the heads to increase flow. A guy could port the intake runner and it would act like you installed a bigger cam. the motor could breath in more air and make more power. Until the port size is increased there will be no more power gained from the BRA mod. in fact, you could take your heads off have them ported and you would be set to make some serious power. extreme caution should be used when porting your heads. Keep in mind that smaller is better than to big. your motor will be a dog if you over port the heads. I do not plan on porting my heads. not unless i get a hard on to try to be the fastest naturally aspirated big V-twin in the USA and that wont happen as there are far bigger S&S motors that can make some serious power. not that the 113 cid engine couldn't surpass them. it just wont happen on my dime. i dont have any dimes left. LOL.
 
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