Any one out there have issues with a Big Bore kit not giving them the power they were told\expected...?

I have an 06 bagger and had a 95" kit put in by a local engine builder.
He upgraded the cams to the Woods 07 Roller Conversion style with a .510 lift. He also used Weseca pistons and ported and polished the heads. I have a Stage 1 A/C, Rush duals and a PCIII. After all the work, I had it tuned and the numbers show 85hp and 97tq. The tuner said the torque is great but the hp is pretty low compared to others he has seen. He told me that the SE stage 1 AC is not sufficient to support any higher hp. Before I did the work, the builder said the AC was fine and I should be at 100hp with this build.

I am real happy with how the bike performs with 2 up riding now. I am able to crack the throttle and not have to wait for a response, and I can pass without down shifting. Just looking to find out if I was sold a bill of goods, if the tuner is full of it, or maybe 85 hp is what you get with a 95" kit. I have talked with several people who say you should be able to get 95hp easily out of a 95" kit without any head work done...

Any help is appreciated...

 

From the sounds of it, you have the Woods TW6-6 cams.

What compression ratio did he set the build at?
Did he measure the deck height, or combustion chamber volume?

Flat top pistons or domed top?

If the build was done "right", the CR at 10:1, a better exhaust, and a good tune........then you should be able to get 100/100 out of it.

Steve

 

Steve..Thx for the reply.

Yes they are the TW6 cams... According to builder, he spoke with someone at Woods and they recommended them and 9.5:1 flat top pistons. Not sure about the deck height or volume.

When you say better exhaust, can you clarify. Fuel Moto recommended the Rush based on the build....?? I was looking at Rinehart or FBI duals, but they said these would be just as good...???

 

I think 9.5 to 1 is a little low for the 6's. lot of 100/100 builds with se ac.

 

Woods TW6-6 cams like 10:1 to 10.2:1 for a CR. Less then that and they won't work as well as they are capable of.

A better exhaust would be a 2-1.........they give the best overall performance. True duals are known to have some low-end power issues. On a bagger you really want all the low-end power you can get, and a 2-1 gives it to you as well has top-end.

If you are at 9.5:1, which is impossible to tell without measuring the deck height and head combustion chamber size, then that would explain why your numbers came in lower then you expected.

Steve

 

what exactly did he do to the heads???
Tq is a little low and HP is at least 10 off.
running the lower compression with that cam might be a problem.
andrews 37 with that compression might be a better match.
need more info on the heads

 

An easy/quick fix to compression being too low would be to install a 4 degree advance gear, this wouldn't raise power too much, but it would add torque to the low end by raising CCP. might work good for you on a bagger...

 

Thanks for all the info guys....

SEDeluxe...Not sure what he did to heads. He said ported and polished but kept the stock valves and springs.

Sounds like all agree that the CR is on the low side. When we first discussed this, we talked about the 10.5:1 pistons, but builder said Woods recommended the 9.5:1...

At this point, if I go back to builder, would it be better to change cams to better work with the 9.5:1, or change pistons to better match cams???

 

Steve...That's a nice looking bike. I like the Doherty A/C. Did you see any gain going to an open filter? I have the SE stage I and the guy who did the dyno tune said the SE Stage I was not adequate for my build...

 

I have the SE 10:5:1 and head work done, I originally had a SE257 cam the #'s where there but so was the ping. I, like you was expecting different things. I built the motor I wanted for my softail for the bagger and the softail had the better bagger motor. Go figure~! I recently changed cams and tell you what HUGE difference!

I am pretty sure that is why they refer to this in the race community as testing it is all about getting it dialed in to what you like. Keep at it you'll get what you want.....