Running a powervision on my build and after many autotune runs i finally broke down and took bike to a respected dyno tuner.
Build is wiseco 106 pistons with stock heads ( no shaving or headwork) 0.30 headgasket. 204 cams
on a 2010 roadking. (Has stock 50mm throttle body and stage 1 intake)
ran decent with rinehart true duals but having the power bug i switched for a propipe.
Love the sound and feels good but a stock 103 can stay with me. (Hence the dyno tune)
first thing out of gate tuner complains about pipe.
(I had drilled a 1” hole in the cap of the baffle)
pulls baffle and welds up hole.
Bike won’t brake 80hp and 80 lb/ft and falls off around 4000rpm
then he says my compression must be in the tank.
We test it and I’m cranking 210psi hot
then he says somehow the 30 tooth output pully is screwing up the pulls.
Anybody have anything they can offer?
i swear it felt better before i took it to this guy but he’s had me try multiple maps and then wait a week before i go back.
No pinging and no ion events. Pulls pretty good from idle to 3500-4000 rpm then feels like its out of steam.
Last thing he recommended was to buy a better pipe but I can’t see how thats the way to go when so many are happy with propipe.
Is it the “plug” in the baffle?

 

Do you know what both front and rear compression were? Maybe cam timing is off?
Something isn’t right if it only makes what a stock 103 makes.
Here’s my thought. The 204 cams makes really good cylinder pressure which makes them “ping” sensitive under load especially in a hot, loaded bagger trying to pass on an uphill pull.
Now increase the compression with a .030 gasket and MAYBE the timing has had to be reduced to the point where the predicted performance increase cannot be realized, caused partially by the fuel quality we have today...especially the states with ethanol blended swill.
Interested to know what if any timing compensation had to be made for the 204 cams.
Bob

 

210 psi both front and back cylinders. Timing has not been reduced at all and have been monitoring for ion events and audible ping. Nothing at all.
With original true duals (rineharts) the top end power was phenominal but bottom end wasn’t what i expected. Many auto tunes later went with propipe and bottom end increased alot but top end suffered.
Still was autotuning so started “opening up” the baffle plug in propipe and got better the larger i went.
Decided to pay for dyno tune and first thing guy did was pull baffle and weld up hole.
Back to no topend power.
Im in ontario canada so I don’t get florida/texas heat so wasn’t super worried about hot ping.
Not sumping. Cams timed right. Motor runs cool with no noises. Compression test higher than i expected.
I think th bottle neck is the baffle plug.
Tell me I’m wrong...

 

You’re wrong.
That pipe easily handle more than 100hp and you’re 20hp short short of that.
From tuning these bikes with these pipes we’ve found covering a row or two of holes in the stock baffle the results were better down low and didn’t cost any power up top.
If you are 1 tooth (main drive gears) advanced on cam timing it may just provide the cranking compression results you encountered. This would maybe help bottom end but cost big time on the upper end of rpm.
Bob

 

Amazed it would even run if cam timing is off. I’ve run this motor for 2 seasons without touching cams. Should i open it and check? Think its really a possibility?
really appreciate your help!

 

What I see is a lack of torque. I believe, if all’s well, it should make 100t+tq.
As far as cam timing is concerned...depending on the cam design an overall 1 tooth retard or advance error during installation may appear to produce a decent running bike, especially when you have nothing to compare to...other than a stock 103 that keeps up with you.
So you have a 103” over-bored to 106” w/stock heads, .030 gasket, SE204, stock tb. I have to believe, with a proper tune, should make 85+hp and 105+tq
Sumpin’ ain’t right...which brings me to the next possibility based on your description of power going away after 4K rpm.
If oil is not getting returned from the engine as fast as newer/cooler oil is entering the engine the flywheels begin to “dip” into the built-up oil at the bottom of the crankcase. Just like a boat in water, there’s an incredible friction from the oil contacting the flywheels killing power, especially in the upper rpms.
That said here are two very simple tests...
1. Run bike at idle until completely warmed up (bottom of engine crankcase is hot to touch). Shut it off and drain whatever oil is found from removing the plug at the bottom of the crankcase. It’s an Allen plug. Measure the oil. Replace plug.
2. Run the bike for at least 1/2 hour as you normally ride so you get it good and hot after some power runs through the gears.
Now go home and don’t let it idle once you get home. Repeat the drain and measure what you get. Careful it should be really hot oil coming out.
There’s a reason it’s called a “Dry Sump” system.

 

Have you had the cams or oil pump out for any reason, lately? I also have to second the fact that your issue is not the pipe, and he actually did you a favor by welding up the 1 inch hole. I have a lot of time modding that baffle(confirmed increases on the dyno), and uaually i have a few small 3/8's hole in it, mostly to fit the sniffer lines up each head pipe.
I would second the idea that you may have a sumping issue going on, follow the above outline and see what you get. I agree that you should be getting better numbers also, but your pipe is not the issue.
marco

 

Appreciate the help guys. Working on it now. Hopefully have answers in the next day or two.

 

just for the record, i made the broke the o-ring on the oil pump mistake myself, couldn't believe i had done it, first time i'd ever done it since the TC's came out, the bike was down 35hp on the dyno, so it is a viable possibility and something to confirm. map was good and i was scratching my head trying to figure it out, the bike was putting out 90+ hp, before i went in and made a cam change and added heads that hoad been worked, i knew it should have been breaking 100. after i went in and found i'd messed up the oring, and put a new one in , the issue was cured. The sumping issue, a big pain in the butt!!

m

 

Going in chest to check cam timing and oil pump.
Really appreciate input guys!!!!