VT1100C up to 96 Cams


  • Hey guys...Im new here, live in the UK, i have an N American imported 96 VT1100C Shadow 4 speed and been looking at the various models from 85 up to and including my 96 model....now....ive noticed differences in the power outputs for different years...i know the 85/86 ones were higher comp ratio/ different cams, timing, bigger carbs, different heads too?? etc....do these early camshafts fit the later engines? 

    Also ive notices different power from the detuned 87 models compared to my 96 i.e. 67hp from 87 88 models, but only 60 from my 96...is this down to the different carbs? (I noticed carbs on the 87s were slightly bigger, is that right?) or timing or cams? If this is the case...if i fit cams from an 87 88 into mine, will it help pep it up a bit...im not a small bloke and with the good lady perched on the back it can feel a bit sedate...if you know what i mean...i have ultrasonically cleaned and rebuilt the carbs, fitted a set of Delkevic slash cut slip on pipes, fitted a K&N air filter and jetted accordingly, she runs very sweetly having only covered 25k miles.....that work in itself has improved the feel and response to the motor.

    Im not looking for anything crazy, just another 7-8 hp and, if i could get an increase in torque would be even better...any thought on this from the tech heads?

    Cheers Paul



  • @Paul Cullum get rid of the stock intake and get open pipes youll have more than a 7hp increase.

    The stock 1100 in 96 was choked down to be a reliable long living mild bike. they wake up if you get rid of the stock intake and sexhaust and tune them. 
    the 85-86 and some of the 87 year models are not the same as the 2nd generation engines. they are very different and the cams are not interchangeable. if you look at an 85 and 96 side by side, you will see how very different they are just on looks alone. the carbs have pretty much always been the 36mm keihins with differences being in the choke, vacuum setup, air cut valve, that kind of stuff. 
    a cam isnt going to change your bike the way you think, plus you cant just drop a cam in an engine and expect there top be a magical upgrade. 
    youll need to check pistont o valve clearance. even if it fits, you can still mash the valves into the piston. 
    valve to valve clearance, if theres more overlap on the cam, the intake and exhaust valves can get real friendly with each other and result in a very bad day for you.
    rocker arms, lifter condition, a cam can destroy worn parts really fast. so youll have to check rocker arm wear patterns, lifter wear, cam chain guides and tensioners. if you smack a fresh hot cam in a valvetrain thats already tired, youre gonna have a bad time. 
    Oil supply - cant really do anything about this on a VT1100, but some cams will demand more oil. 
    Cam timing - just because a cam seems "drop in" that doesnt mean its optimized and ready to run., Tuning -biggets complaint is that people drop a cam in and say it sucks, but no your tune sucks LOL gotta tune again!
    a cam change may mean the bike requires more airflow, but if you still have a corked exhaust, tiny restrictive intake, restrictive airbox, then the cam will be very disappointing. 
    and heres more fun! Big cams will bleed off cylinder pressure at low rpm, due to the intake valve closing later.  if compression is too low, it will feel very soft. rarely is a cam just dropepd in, a cam upgrade isually requires cam +compression not just cam. 

    also may need to address ignition timing and spark needs, more airflow and cyulinder fill can change what the engine wants. so thats fun! 
    i could go on but a cam swap isnt just that easy if you want any kind of improvement. 

    at any rate, you can wake the bike up with intake and exhaust and a tune but if you really need more power i would suggest looking at the VTX1300 line. much more power and plenty of giddy up and go for 2 up riding! 

     


  • Thanks for that...an interesting read...yes i understand about the cam changes, as done it with classic Mini engines etc where you need headwork and tweaking timing to really exploit the cam to its fullest, and yes i had noticed the difference with the early motors...actually if open pipes and intake give 7 hp+ then i'll be happy with that tbh...i love the bike and so does the lady, so thats all the info i need TJ, thank you! 🤙


  • Actually, just one thing....i looked at your open pipes and, for me, lovely! But the mrs wont want them blowing up her legs! or the noise in her ears 😂  Are the std headers restrictive in themselves or is it just the crappy mufflers? As i say, the Delkevics ive fitted are very free flowing, and exit past the passengers legs which is good, so i'll probably stick with them, but i'll def junk the inlet setup and go for velocity stacks.


  • @Paul Cullum the pipes wont blow up her legs, and they have internal baffling, just fyi. the standard exhaust set are just extremely restrictive. 


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