Is it worth it convert from 2 carbs to 1?

Discussion in 'Road Warriors' started by ParrotheadJeff, Jun 20, 2013.

  1. JerryH

    JerryH Banned

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    Short term maintenance on my Vulcan 750 consists of changing the oil and checking the tire pressures. Spin in filter. Hydraulic lifters so no valve adjustments. Spark plugs and air filters every 20,000 miles or so. Coolant change every 2 years. That should be about it. But then there's the final drive. Very poor design by Kawasaki. You have to tear the whole rear end out of the bike to lube the splines every 10,000 miles. Rear wheel, gearcase, swingarm, shocks, brake parts, and complete exhaust have to come off. Taking your time it's a 2 day job. I wouldn't mind so much if it was every 20,000 miles, I'd just do it when I replaced the tires. But you have to do it twice as often as replacing the tires, or the splines will chew themselves up, requiring a new final drive unit and drive shaft, about $1500. I did not know about this with my first Vulcan 750, but I liked it so much that I bought the '02 knowing what I was in store for. One of the first things I did when I got it home from the dealer was to tear it apart and do the splines. Sure enough they were bone dry on a brand new bike.

    These bikes were made unchanged for 22 years. The most likely reason there are not that many of them still around is that most owners never knew about this issue, destroyed their drive splines and gearcase, and sold or parted the bike out rather than spend the money to fix it. They also had issues with the automatic cam chain tensioners, but a set of manual tensioners at around 15,000 miles fixed that problem permanently.
    #21
  2. conchscooter

    conchscooter Long timer

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    Back on subject. I don't know why reducing the number of carbs from two to one would increase power. In the old (old!) days Triumph offered a single carb Tiger versus a twin Carb Bonneville. The idea was greater simplicity in an era when carbs went out of tune easily (Amals did anyway) and lower purchase price. Greater power went to the two carb Bonneville. Perhaps there is some other reason why 700 dollars buys a paltry extra few horsepower. $700 could easily buy you a whole motorcycle if you aren't too fussy. Gioven your financial situation look elsewhere for simplicity and ease of maintenance. (HD does low maintenance if you can trade in for a lightly used one).
    #22
  3. Birdmove

    Birdmove Long timer

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    I think you get more peak HP with two carbs, but better low end and torque with a single. I'd rather have a better low end myself on a twin.
    #23
  4. JerryH

    JerryH Banned

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    You will not likely get more power at all by using a single carb on a multi cylinder engine, but you should get more torque. But the big issue is simplicity. The simpler something is, assuming it still works, the better it is.
    #24
  5. ParrotheadJeff

    ParrotheadJeff Class A CDL

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    Thanks for all the replies :D

    After much consideration, the simplicity and possible gains would be nice, but I've come to the conclusion that they're not worth $700. I think I'll save that up for other things.

    Thanks again :thumb
    #25
  6. JerryH

    JerryH Banned

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    It looks like the valve adjustment on the V-Star 650 is fairly straightforward, just a lot of work removing and replacing things to get to them.
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  7. OConnor

    OConnor Bad juju

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    I guess I hadn't heard a single carb giving more performance than two unless the two are not tuned properly.
    I thought this bike was meant as low-cost transportation? I have trouble spending that kind of money on the FCR's for my SV race-bike.
    Speaking of the SV; I only paid $1300 for it to start with, save your money and put it toward another bike.:deal
    #27
  8. ParrotheadJeff

    ParrotheadJeff Class A CDL

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    Exactly. There's a lot of stuff that has to be removed and replaced :bluduh The single carb setup would eliminate the need to remove the carbs and all to gain access.

    It's low cost transportation to a degree - I also have a Chevy HHR that I can't wait to sell once it's paid off in a year or so. I need a car to get my 10 month old daughter to different places. I only paid $1400 for the V-Star to start with, but I really like it and wouldn't mind spending some money to make it easier to work on etc. :wink:
    #28
  9. OConnor

    OConnor Bad juju

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    I'd just ride it like it is, after jetting of course.
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  10. alekkas

    alekkas Been here awhile

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    Since you are asking ...

    700 is too much to spend on that bike unless you are doing multiple farkles that you MIGHT get a little back on - like backrest / shield / boards / etc... Even then, probably not. Ride cause you like it. Soon, you will be in another bike based on the experience of most with their first bike. IMO
    #30