2006-07 yamaha R6r build went wrong

Hello 13x forums

Looong time lurker, first time poster.

I never needed to post because i usually found what info i was looking for using the search function.

I defiantly need some help with a engine build

Background story about me.

I'm just an ameture racer in southern ontario, and my first time building a motor. bike is a 2006-07 yamaha r6r

It was stock, so i decided to see what power i can make.

Things i have done.

New pistons and rings

Knife edged the crank, and had the crank , clutch, magneto, flywheel, rods, and pistons balanced.
put a .45 head gasket in, and had the head re surfaced.

Lapped valves with throw away valves, (didn't use stockers)

Polished my exhaust runners, and sanded down the casting on the intake.

i degreed the cams to 106 intake with PTV being 1.00mm , and exhaust at 107.5 with ptv being 1.40mm

Bike fired up, and off the dyno it went to get a tune.

I have a Bazzaz with a flashed ECU, full hindle pipe, and new yamaha air filter.

after a engine break in, fresh oil and filter, the pulls started to come.

@ 65% throttle, the bike made 90 horsepower.

@ 100% throttle the bike made only 101 hp.

All dyno pulls were done with avgas (100LL)

Pretty disappointing that i made less than stock.

I never actually got a baseline tune before i dove into the motor.

The bike sounds angry as all hell, and screams like a banshie

Few things to note, the rear tire was spinning on the dyno during its 100% pull.

The torque curve comes on very strong down low, thinking about nudging the intake and exhaust cams a few degrees.. 107-110

The 06 race manual suggests 106 in and 109 exhaust, but in 2007 with the same motor, it suggest 110/110

I'm going to do a track day next weekend, and see how the bike actually feels, and decided wheather i need to change the cam timing.

Attached is my dyno sheet, and links to info i received from other threads.

http://forums.13x.com/index.php?threads/2007-r6-cam-degree-help.253936/

http://forums.13x.com/index.php?threads/08-r6-engine-rebuild.300322/page-2

 

why avgas?

 

Av gas sucks, get some fuel for surface machines unless you are going to drop it from an airplane at 20,000ft while at 12,000 rpm.
Did you have the valve seats properly cut?
Lapping in valves on worn out seats is a total fail IMHO.
Here's an idea, after you get a proper valve job, cut the valve relief pockets deeper and run 101 int and 107 exhaust.

 

i'm running avgas to avoid detination. I live by airport, so it is readily available, and i feel that running non ethanol 91 might ignite early.

i didn't cut new seats, i just did what the manual suggested by 'lapping' them with a throw away valve.

i will try a leak down test later to see if they are leaking.

 

I promise you, av gas is a major mistake you are losing a ton of power running that crap.
I know, it used to be popular 30 years ago and was completely debunked back then, use your google-fu grasshopper.
If you are that paranoid about high speed detonation, run cold plugs and learn to read them.
Best plan is to run super unleaded and mix three qts of that with 1 qt of whatever VP C12 is called these days.
You will get the fast burn speed that you MUST have to make power and still resist detonation.
If you start to pick up "pepper spots" on the insulators, run a bit richer.
As to valve seats, the fast guy's tuners spend hours and hours getting the seats perfect (along with seat width, and custom throat and top angles) it makes a big difference in high rpm power readings.
Now on to leak down testers, the one most guys have don't offer much info because they pump high pressure air in the cyls, which pushes the rings into the cyl wall harder and also pushes the valves into the seats somewhat.
You need to use a low pressure or aircraft type leak down checker.

 

Thanks for the advice Tunersricebowl

You posted in a lot of the threads i have looked up, but they were so old, that i didn't think you would be around anymore!

Thanks for the advise on Avgas. Most google searches came back with 11 pages of people bickering back and forth about the subject. Made sense to use it, but i will try the 91.

In Canada, I can get shell 91 v power with no ethanol, or 94 with ethanol.

As for engine work, i am out until the fall. I will defiantly look into cutting new valve seats for the next tear down. I had a budget in mind for this build, and didn't want to go hog wild for my first engine build.


I really thought my problems was with my cam gears. I timed them to the piston, as was recommended by a few engine builders on this website.

I feel as if the exhaust intake is opening to early, not allowing enough cylinder pressure, and giving the bike to much overlap

thoughts?

 

I can't tell you what lobe centers to use on injected R6, I'm a true old timer, you know a carburetor expert etc...
(I am trained in digital fuel injection and computer controlled systems, but that's all car stuff...)
As to lobe centers on the FI R6, I know they closed up the squish to you can't run the good numbers anymore, you have to keep the lobes/valve tips away from the pistons.
Running the squish lower than stock to me anyway is even more of a penalty because you have to keep the lobe centers/valve tips away from the pistons, so you are gaining torque from higher comp rather than advancing the intake like we used to and then suffering with late intake timing...just my opinion, it seems to work pretty well..
I can't recall what the stock lobe centers were on yours but as for me, I would run the valves as close to the pistons as courage will allow.
Tighter is faster, until you miss a shift or over rev on a back shift that is...
Again, on fuel run super unleaded and top it off with some leaded race gas.
Whatever you do, stay away from "octane booster", that stuff wipes out shell bearings.

 

Just a heads up on the av-gas/higher octane topic. With these bike engines you're really not going to be running into many knock issues where you need the higher octane. Keep advancing timing and you're gonna start dropping torque before you knock, even with higher than stock compression. This is coming from Formula SAE, a popular student competition that uses a lot of motorcycle engines. People are running much higher compression than stock on just pump gas. Look at something like MR12, a super popular race fuel in road bikes RON-MON/2 of 93.

 

thanks for the info


Now i did miss something in the story above, which is really making me guess this AVGAS decision.

When i was doing pulls at 65% throttle and making 90 horsepower, it was a mix of 91 and avgas. Maybe the 91 was the reason the bike was making that power at that throttle position.

we took a break, and i filled the tank with 100% av gas

 

The problem with AvGas in your situation is that its octane rating is TOO HIGH - yes, that is a thing! The same chemicals that prevent detonation also slow the burn rate, losing power. In order to regain that power, you need to do other things like increasing compression or advance. This is a street-bike engine; use street-bike gas.

 

yeah... you got the necessary primer on why not to us AV gas. Maybe as a storage fuel but not as a performance adder.
VP makes a 93 octane fuel thats about $7/gal US if you want a consistent non enthanol blend.

 

Just one more point to ponder - TZ125 and RS125 GP bikes used to come from the factory set up for AvGas. (They would typically be bumped and skimmed to use VP C12 or equivalent) These are engines that will detonate themselves to shrapnel in short order running pump gas of the highest rating. I rather doubt your R6 engine is as highly tuned as a privateer-level GP bike.

 

hahaha, this thing was made in a basement over the winter months in Canada. Doubt away.

 

Great read!

 

tire was spinning on the dyno as you were doing 100% pulls ? so ... how are you able to quantify any of the info you were looking to get?

it might be better than you thought, but as many stated, i don't know of anyone running av gas for these bikes. Too much octane makes less power. as jboylen pointed out, MR12 ..king of power in available fuels.. is not higher in octane than any available pump gas. it's all the other additives and oxy added that make the power. You do retard timing at higher rpm though to get best power from it.

Are the numbers of 90 and 101 hp compared to other known good motors? maybe that's how his dyno reads (but that does sound low even adjusting 15% for some dynos)
The 2006-7 cams are different from 08-16 .. the cam timing numbers in the kit manual have worked well but i would stick with year specific cams/numbers.

sounds like a cool build and ya had fun with it.. hope ya get it sorted. On the plus side, it didn't blow up on the dyno so you musta done something right.

 

When i saw it spinning on the dyno, i thought this thing is about to make some serious power!... no so much though.

I'm going to say it was the cold dunlop slicks that might have been causing the slipping.

If S1000 don't slip, then it has to be the cold slick.

He said that the motor with boltons make about 109hp
He belives is was the head work, was told to leave the head alone.

I didn't port it, i just cleaned up the intake and exhaust ports.

I built this motor out of spite from a previous engine builder on my zx6r, that gave me 2 paper weights. This was an awesome experience!

I had two goals in mind with this build .
1) it has oil pressure on start up
2) it doesn't spin a rod bearing after 20 mins of run time.

the engine i paid for had number #1 happen, and after fixed #2 happened

 

you can run avgas much much much leaner than you would expect also.

run ridiculously lean it behaves as 100 octane. run rich , it behaves like 130 octane.

 

I am going to side with the 'lose the avgas' crowd. Here is why.....

It is made for larger displacement engines that are VERY old tech that run at (more or less) constant throttle and are (by bike standards) VERY low revving.

My suggestion would be to run the best NON-alcohol added premium fuel or some form of 'low end' race fuel. It will not be cheaper, but it is pretty much horsepower in liquid form compared to 100 LL avgas.

Good luck !

 

Your cam timing is fine. Changing to the numbers you posted will not add anything significant. What was the head thickness after you surfaced it? How much was removed? What was the squish dimension at the front and back (or an average of those two) on the pistons? Have you performed a leak down on each cylinder?

 

i never actually measured before and after when the head was re surfaced.

i'm also not to sure how much was removed. enough to take a bit of metal off the the thermostat housing. In hindsight i should have taken a measurement. I remember reading (from you actually) not to take too much off the head. i feel that if i took to much off i wouldn't be able to run my LC were they are?

did not measure dimension squish either.


and also negative on the leak down test yet.


.....and now i feel embarrassed lol