204 installed
Road Warrior
Joined: Mar 2010
Posts: 1,505
Likes: 56
From: Vancouver Island, British Columbia
I dont have your exact cam but have a "torque cam". I was getting 41-42mpg before and 38-39 after the cam install with tune. I do smell more gas now but I attribute that to the engine's new desire for power... I went up over 20% in torque and hp. Do you want oerformance ot fuel economy. You don't get both.
Ultimate HDF Member
Joined: Jun 2009
Posts: 6,899
Likes: 3,412
From: OH
I think the mileage largely depends on where the cam hits in relation to the speed traveled most with in reason as wind drag takes over eventually. It seemed that way from my experience. A well tuned motor should consitanlty pull 40mpgs if not better cruising. Getting on it is another story.
Grand HDF Member
Joined: Nov 2004
Posts: 3,917
Likes: 184
From:
204's are a bit hard to tune for some people, the intake is advanced 4 degrees but if I had a thundermax id be concerned as well. I have seen too many issues from those tuner's to run one if it was free. I'd get me a Power Vision and get the bike tuned from a good tuner, or you may be able to buy a license from a Power Vision dealer at $150 and get it tuned that way, that's what I did.
Road Master
Joined: Apr 2007
Posts: 1,216
Likes: 242
From: Northern O H I O
I have a Power Vision and I did Auto tunes. Bike runs good power-wise, gas mileage is good too (38-41) but it's also hot and from all I've read, the 255 CAM is partly why that's the case. The leanness of the fuel is the other part.
Sure, you can throw a bunch a fuel at the tune and it will reduce the heat, along with your gas mileage. 35mpg and under is just too low for me and I found the only way to get the bike cool enough was to increase the fuel so much that my MPG went down that far. Thus, 204's are being put in over winter and it will be tuned by a pro.
Last edited by xmen9c; Nov 20, 2015 at 12:50 PM.
I have seen where some people have had an increase in mileage with the 204's and the proper tune. Elevation and Atmospheric conditions may play a part in all of that, but I agree with Xmen and a few others from this forum that you can have both nowadays. With carbs and cams of old you could not, but look at the vehicles that are getting massive power and still streetable with good fuel mileage.
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