ROAD KING ENGINE UPGRADE

[Patrick]

Dear Mike:

I would like your advice on what I should use to upgrade the engine on my bike. I own a 2003 HD Road King Classic with a fuel injected 88 cu inch engine and Stage 1 upgrade (9500 miles). The bike has Rinehart True Dual exhaust. I am looking to ugrade with your Boss 95 package. I do mostly medium length tours and would like to select a gear-driven cam that will give me increased acceleration for passing and good overall performance. Can you please give me your thoughts on appropriate cam choices and any other upgrades that might be appropriate to accomplish my goals? I am also thinking about installing the Quiet Baffles in the True Dual Exhausts and would like your opinion on that. Finally, I was toying with the idea of upgrading to a 6-speed transmission and was wondering if you had an opinion on whether HD or Baker would be better. I was considering doing the engine upgrade immediately and then the transmission possibly in the future depending on how the new engine performs. Is this wise or does the engine configuration vary significantly for a 5 or 6-speed transmission? Sorry for all the questions and thank you in advance for any guidance you can provide.

[Mike]

The Boss would be a very good upgrade. It will work very well with the changes you've already made. The quite baffles will lower peak HP numbers but will also boost low RPM torque, better for passing without as much need for downshifting. When going to gear drives with this combo, either the Knightprowler TW6HG or T-man TW600's would be excellent choices. Less expensive option would be the S&S 585 kit but will not quite as powerful as the above. As an H-D dealership, I would recommend the SE 6speed vs. the Baker. Less expensive in both parts and labor cost's (easier to install). Baker has a great rep. and would work equally as well. Tuning in theory would be different due to change in load for each RPM/TP (M.A.P. values will be slightly different). In reality this diff. is very small and I would not neccessarily recommend a re-map with the tranny change, if the bike was properly mapped with the 5 speed. The 6speed will lower dyno numbers by approx. 4 hp and so should be accounted for in hp estimates or expectations. Other upgrades would be the SE clutch diaphragm spring and SE Race Tuner/dyno break-in/custom mapping. At 9500 miles I would strongly recommend new tappets with the new cams, check to see if you have the "B" oil pump (if not advise upgrading to it), metal rocker cover breathers (if not already installed) and our oil bypass spring (in the kit).
Thanks, Mike