Motorcycle Club » Star 1100 Classic & Custom

carb. versus fuel injection

13 posts from 5 voices
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  1. donjlip

    How much does the weather effect carbs as apposed to fuel injection. I swear my 1100 runs like Crap in hot humid weather. Or is it just my imagination Thanks Tony

  2. quicgmicg

    It does have an effect. There will be a little less air and a little more water (which doesn't compress).

    Probably a slight adjustment (1/4 to 1/2 turn) of the PMS screws will take care of that.

  3. donjlip

    Boy I hate to play with carbs. I Like this bike and I had every make out there Including a HD FL with carbs. If they made a fuel injection system for my 1100 I would spend the money in a minute

  4. einzdan

    How does the 1100 handle the heat.

    I just recently got my 1100 and my commutes to work are 45 miles each way.

    Right now the temp is in the upper 90's and the humidity is about a gazillion percent.

    Will I have any issues in this kind of weather when I'm sitting on the highway in rush hour traffic, tooling along at about ½ mile per hour if I'm lucky, and if so is there anything I can do to ease the stress on the machine?

  5. quicgmicg

    It's really not all that bad. I'm thinking one little tweak and you won't ever have to worry about it again. There is a ton of free information available on these things to do it yourself, or if there is a GOOD bike shop in your area, check with them.

    FI is great, until something goes wrong with that too....then it's not just a's a ton of cash too.

  6. quicgmicg

    How does the 1100 handle the heat. I just recently...
    I'm in Arizona.....110 - 120 degrees. I ride all the time without issue. Even in our wet season which is now, we have very high humidity. I just run a little heavier oil (20/50 Royal Purple) and it handles that heat just fine. I do try to minimize the stop and go stuff as much as possible (not hours on end) and I've not had a problem.

    It's simply a matter of getting your machine adjusted to your environment.

  7. donjlip

    Thanks Mick maybe I will do some research. I wander with all of this corn gas out there maybe premium gas would help in this type of weather Just a thought.

  8. quicgmicg

    Hers is some really good reading...

  9. donjlip

    Talking about a whole lot of info.This gas we use sucks I just ordered a half a case of Sea Foam and i will be topping off more Often and draining fuel bowl.I guess Higher octane is not the answer just fresh gas

  10. quicgmicg

    It is a lot of info...I use that site all the time.

  11. lorzpan

    Carbs are ok. In my opinion, better to work on since you won't be messing around with electronics like you would with EFI. One less thing to worry about, in my opinion.

    That said, I just had my bike's valves adjusted and carbs sync'd and cleaned and now it runs absolutely perfect. No vibes till around 85 mph! Before it'd get vibey at around 65-70 mph.

    So, just have your bikes looked at. Maybe it just needs some set-up work.

  12. bkman

    Carburetted bikes are definitely cheaper to modify, and build. I think it is a matter of preference, although it is hard to argue against the superior efficiency and (most often) power advantages of EFI. Also, the EFI bikes tend to start easier and run better when cold than a bike with a carb, but that has a lot to do with the way the carbs are tuned. I would think a good carburetor setup will perform similarly to an EFI setup, it just will not adjust to changes in altitude or air temperature (density) like the EFI bike would, and the EFI bike will probably run smoother and idle better when the engine is cold.

    The more sophisticated EFI systems are dynamic - they adjust constantly to air density, temperature and pressure, as well as rider input (throttle position and engine load). Carburetors are pretty much static devices - you set them up for a happy medium, based on the range of riding conditions you generally encounter and you almost never achieve the perfect mixture. This usually results in slightly worse fuel economy, and slightly less ouput. In my opinion, it hardly matters when your power-to-weight ratio is that of a motorcycle.

    To me, the REAL difference between EFI and carbs would be in the cost of modifications. I put a complete intake / carb and exhaust on my bike for just over $500. An EFI bike would cost more like $700 once you buy the fuel processor and other bits necessary for SOME kits. I know there are those who say EFI systems can adjust to exhaust changes automatically. I am not sure I'm convinced. I've seen exactly three EFI bikes that had exhaust systems put on with NO changes to the EFI system. They ALL popped a LOT at low speed and I don't think they ran as well as they did stock (after riding with these guys). This could be three isolated ocurrences, and I won't argue the point too much because none of the bikes were mine. If I had to guess, though, I'd say that exhaust modifications to EFI bikes probably throw the fuel curves off pretty significantly, and adding an inake kit DEFINIETLY would. So, to do the same mods on an EFI bike would definitely have cost me more. Is it worth it? Perhaps to some. I was looking at an EFI bike when I bought my V-Star last Summer. I chose the V-Star because it fit me better and it seemed like a better machine, overall. The carburetors were not that big of a deal to me then, and they still aren't

  13. einzdan

    My previous bike was a Suzuki, which had EFI, and from posts on that forum from members who changed exhausts, and in many cases the air intakes had to be modified at the same time, there was no automatic adjustment by the ECU, it had to be remapped; and you're right PG it was at a cost of reduced gas mileage.

    But hit the starter button on those, no matter what the temperature, and in 2 turns of the engine they were purring like kittens.


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