hard starting
Welcome guest, is this your first visit? Create Account now to join.

Welcome to the Motorcycle Forum.

Register ButtonIf this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed.

Page 1 of 3 123 LastLast
Results 1 to 15 of 38

Thread: hard starting

  1. #1
    Newbie
    My Bike(s)
    yamahaxs1100
    Location
    Durban , RSA
    Posts
    13

    hard starting

    I have a 1980 Yamaha XS 1100, and have had no problems starting for 9 years, start instantly, but a year ago it started getting hard to start, if I use the choke it won`t start at all, but if I pour some fuel onto the air filters, it starts almost immediately, even if I pour fuel onto the air filters and use the choke, it won`t start, I`ve cleaned the carbs, checked floats levels, but can`t find the problem

  2. Remove Advertisements
    MotorcycleForums.net
    Advertisements
     

  3. #2
    Super Moderator

    My Bike(s)
    Vulcan 900, Can-AM Spyder
    Location
    Ocala, FL
    Posts
    10,947
    Welcome.
    How's the battery ?
    A weak one can sometimes cause this.....and yes it LOOKS like a fuel problem.

    If it was running some I'd suggest Berrymans B12 Chemtool in the gas.
    But since it isn't some professional help might be required.
    Don't believe everything that you think.

  4. #3
    In Training
    My Bike(s)
    CBF600SA
    Location
    Nanaimo, BC
    Posts
    133
    What colour is the gas coming out of the carbs? A 1980 motorcycle may have some rust issues blocking a good fuel flow.

  5. Remove Advertisements
    MotorcycleForums.net
    Advertisements
     

  6. #4
    M-J Lifetime Achievement Award
    My Bike(s)
    Yamaha MT09
    Location
    Perth WA
    Posts
    6,142
    My first thoughts too ^...fuel lines, and in fact all lines should be renewed if not done so already.
    Smoke me a kipper I'll be home in time for breakfast

  7. #5
    Newbie
    My Bike(s)
    yamahaxs1100
    Location
    Durban , RSA
    Posts
    13

    hard starting, it`s a new battery

    Quote Originally Posted by Easy Rider View Post
    Welcome.
    How's the battery ?
    A weak one can sometimes cause this.....and yes it LOOKS like a fuel problem.

    If it was running some I'd suggest Berrymans B12 Chemtool in the gas.
    But since it isn't some professional help might be required.

  8. #6
    Newbie
    My Bike(s)
    yamahaxs1100
    Location
    Durban , RSA
    Posts
    13
    It`s a new battery

  9. #7
    Newbie
    My Bike(s)
    yamahaxs1100
    Location
    Durban , RSA
    Posts
    13
    I`ve cleaned out the tank, no problems with fuel flow, new lines and filters

  10. #8
    Newbie
    My Bike(s)
    yamahaxs1100
    Location
    Durban , RSA
    Posts
    13
    this is interesting, if I use the choke, it won`t start at all, if I pour liberal amounts of fuel onto the carb filters(K & N filters)it will start almost immediately, if I pour the fuel and use the choke, it won`t start either, if I stop for upto 15 minutes, it will start, if any longer have to pour fuel onto filters again, it I`ve been riding like this for a year now, and want to find the problem.Please help!

  11. #9
    Super Moderator

    My Bike(s)
    Vulcan 900, Can-AM Spyder
    Location
    Ocala, FL
    Posts
    10,947
    Quote Originally Posted by Lionel View Post
    It`s a new battery
    That statement alone tell us virtually nothing.
    Did you charge it fully before using it for the first time.
    That can be VERY important.
    Don't believe everything that you think.

  12. #10
    Super Moderator

    My Bike(s)
    Vulcan 900, Can-AM Spyder
    Location
    Ocala, FL
    Posts
    10,947
    Quote Originally Posted by Lionel View Post
    it I`ve been riding like this for a year now, and want to find the problem.Please help!
    OK now with more information to work with..........

    Take those K&N filters off and go back stock.
    The other side of that coin is that the Prev. Owner might have re-jetted and gone too rich.

    But since you can get it to run with some effort, put 2 OZ per gallon of Berrymans B12 Chemtool in with the gas.
    Run it a few times.

    And I have to ask:
    Are you absolutely sure that you have CHOKE ON AND CHOKE OFF figured out correctly ??
    Choke on closes the plate in the throat; off opens it.
    Don't believe everything that you think.

  13. #11
    M-J Lifetime Achievement Award
    My Bike(s)
    Yamaha MT09
    Location
    Perth WA
    Posts
    6,142
    Idle circuits blocked or clogged...also check the float heights are correct and the float needles are clear and not sticking. A B12 I had ran like a dog and was difficult to start because one float was set incorrectly it affected the whole running of the motor to the degree it felt like a rod was buggered.
    Smoke me a kipper I'll be home in time for breakfast

  14. #12
    Newbie
    My Bike(s)
    yamahaxs1100
    Location
    Durban , RSA
    Posts
    13
    Hi, thanks for the advice, yes, new battery fully charged, actually tried auto battery with jumpers , also in good condition with same results,, carbs have not been rejetted, but why would problem surface after 10 yrs,Yes I know how the choke works, have been riding this model for 25yrs, Bike idles perfectly, so doubt if idle circuits blocked, checked float heights and rechecked them,, put new needles and seats in when I bought the bike 10 yrs ago,I am a mechanic, have completely overhauled previous motors successfully, have rebuilt dozens of bikes and cars, owned a fibreglass boat factory and have done dozens of outboard motors, first time I been stuck like this, I appreciate the advice, and have acted on all advice, even if I have done advised work previously

  15. #13
    Seat Tester
    My Bike(s)
    81 XJ550 Maxum
    Location
    Great North Woods NH
    Posts
    64
    are the carbs cv type with enrichment plungers?
    the pick up tubes in the bowls or the wells in the bowls may be clogged

    Carburetion (4) - 34mm CV butterfly-throttle Mikuni

    the choke lever lifts a plunger and does not open a butterfly in the carb body the throttle opens the butterfly

    clean the bowl wells and pick up tubes
    Last edited by XJ550H; 01-08-2017 at 12:07 AM.

  16. #14
    M-J Lifetime Achievement Award
    My Bike(s)
    Yamaha MT09
    Location
    Perth WA
    Posts
    6,142
    What about the fuel pump filters...if fitted...quiet often the internal ones are non serviceable but a workaround is sometimes easy to do whereby you bypass the internal one with a drill bit and fit an car type inline one...make sure fuel delivery is sufficient if doing this. Also I know the idle is fine but what about the fuel tank vent. Also maybe it isnt fel related and perhaps electrical is the next option to look at...maybe a faulty coil/cable/cap???
    Smoke me a kipper I'll be home in time for breakfast

  17. #15
    Super Moderator

    My Bike(s)
    Vulcan 900, Can-AM Spyder
    Location
    Ocala, FL
    Posts
    10,947
    Quote Originally Posted by Lionel View Post
    I am a mechanic, have completely overhauled previous motors successfully, have rebuilt dozens of bikes and cars,
    If that information was included the first time the replies you received might have been a bit different.

    The "idle jets" are also often called "low speed jets" and it's possible for it to idle OK but stumble just off idle if they are partially clogged.

    I have just two other thoughts: Is the spark nice and HOT at all cylinders ?
    Have you checked for a vacuum leak around the intake manifold ??

    Good luck.
    Don't believe everything that you think.


 
Page 1 of 3 123 LastLast

Sponsored Links

 

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Similar Threads

  1. Hard starting
    By bumper in forum Cruisers
    Replies: 3
    Last Post: 12-13-2009, 10:27 AM
  2. Help in hard starting
    By tryn2hrd in forum Marauder M50 Secret Hideaway
    Replies: 8
    Last Post: 01-04-2009, 08:29 AM
  3. Hard starting
    By ericb445 in forum Roadliner
    Replies: 7
    Last Post: 02-25-2008, 10:28 AM
  4. starting hard, part 2 - staying hard
    By GregR1 in forum Off Topic
    Replies: 30
    Last Post: 05-08-2007, 04:53 PM
  5. starting hard
    By reno1100 in forum Mechanics Corner
    Replies: 9
    Last Post: 05-08-2007, 04:02 PM