Thunderbird 900 Sport MK1 won't start!

Discussion in 'Technical Help' started by StevieP, Dec 14, 2015.

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  1. StevieP

    StevieP New Member

    Dec 14, 2015
    0
    1
    Ringwood
    Hi, I'm new to the forum and have owned a few 900 Hinkley triumphs over the years and earlier this year, at the beginning of summer I bought a minty MK1 Thunderbird Sport 900, which had been stood for some time. It's a 1998 and has only covered 14000 miles. I put some fresh fuel in and reluctantly within a few minutes it started, initially on 1 cylinder and then the other 2 kicked in. I've ridden it 500 odd miles over the summer and it has been fine, going really well in fact, as long as it's started regularly. It's reluctant to go if left for more than a few days, then it does the firing on 1 trick, before the other 2 kick in. I've done the basics, new plugs, oil and filter, but haven't touched carbs or air filter. Unfortunately, now it has been stood for a while again, it won't start at all and isn't even attempting to fire. I've got the tank off and got it linked up to a bottle of fresh hi octane fuel.
    I have checked to see if it has a spark at the plugs and it does. It's fitted with Di ignition coils. I'm unsure whether to have the carbs off, a job I don't relish, as I'm not super competent!!
    I know these are pretty famous for coil failure, but it has a spark, so maybe coils are ok? If anyone can offer any advice, I would be eternally grateful!
     
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  2. thebiglad

    thebiglad Old fart, still riding !

    Sep 25, 2013
    5,064
    1,000
    Central France
    Hi Stevie and welcome to the Triumph Playground. The first thing I'd be doing is have the battery on charge for a couple of hours or more if you can. This may well cure the starting problem, but even if it doesn't you've eliminated a classic starting cause, for nowt!
     
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  3. StevieP

    StevieP New Member

    Dec 14, 2015
    0
    1
    Ringwood
    Hi Dave, thanks for the welcome. The battery is fully charged, also being charged regularly. Its turning the engine over nicely. I've had a look round the forum, looking for a solution and I think I'll probably have to take the carbs and air filter off, which is a bit scary!
     
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  4. sprintdave

    sprintdave Nurse,he's out of bed again

    May 25, 2014
    1,495
    750
    Birmingham
    with the low miles I would think the jets were a bit gummy. Over the summer while you used it did you try any carb cleaner in the fuel, redex, petrol magic etc?? I would have treated the bike to a couple of shots every tank and by 500 miles you would see some sort of improvement I think.
    When you have tried starting a few times with no luck, try taking a plug out, can you smell or see fuel on the plug?? maybe the filters are blocked.
    what is your starting procedure?? most of the carbed hinckley triples will not fire if you twist the throttle. the trick on my Sprint is to ,if it hasnt been used in a while, turn the fuel onto prime and press the middle of the the tap in for a couple of seconds to fill the carbs with fuel, choke on ( now some need full, some half and some none at all, mine is about a quarter). press the starter and do NOT touch the throttle and away she goes.
    On my bike there is a drain pipe at the back, bottom of the engine by swinging arm, mine was unplugged but i found out in another forum it should be plugged so I have done so and it seems to start and runs much smoother tho i do not know why (probably all in my head but thought I would mention it).
     
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  5. stevethegoolie

    stevethegoolie Elite Member

    Oct 16, 2014
    2,452
    800
    East Riding of Yorkshire
    Do you know when the valve shims were last checked? My Trident has never been a bad starter (except for when the battery was on its last legs) but was so much better after the shims were checked/adjusted.
    And yes, as per sprintdave, my bike gets regular doses of Redex which has kept the carbs etc in fine fettle over the 20 years that I've had the bike ... so far ... touch wood!! :)
     
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  6. sprintdave

    sprintdave Nurse,he's out of bed again

    May 25, 2014
    1,495
    750
    Birmingham
    Good call stevethe goolie. I never thought of the shims but T say they need checking at 12000. Some have done upwards of 50000 miles and no shims needed, others have had one or two done and that is it for years. mmmmmmmm

    Also I read on the USA RAT site that premium fuel is harder to ignite than normal unleaded but when it fires it burns hotter or summat like that. Sorry i aint a chemist. BTW I use super unleaded in my bike and petrol magic additive if that helps.
     
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  7. GypsySOHMC

    GypsySOHMC Member

    Mar 18, 2019
    8
    8
    Stoke on Trent
    Mine has fuel {plugs get wet} spark and compression engine spinning over but won't start
     
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  8. joe mc donald

    Subscriber

    Dec 26, 2014
    13,918
    1,000
    slough / burnham
    StevieP
    Try taking the plugs out warm them up and stick a cap full of petrol down each plug hole and try firing it up. you will know if it is carbs and it may get it running if it has enough will to suck the fuel through. If it starts then get fresh fuel and some Lucas fuel conditioner and it will clean itself up internally.
    Regards
    Joe.
     
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  9. GypsySOHMC

    GypsySOHMC Member

    Mar 18, 2019
    8
    8
    Stoke on Trent
    I will try anything, it has new fuel. and the plugs are getting wet.
     
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  10. joe mc donald

    Subscriber

    Dec 26, 2014
    13,918
    1,000
    slough / burnham
    GypsySOHMC.
    Seems we have two here using the same thread. You are losing spark or the filter is blocked or choke blocked. On your bike you really need to check the ht leads and caps the plugs make sure the gap is right and the plugs good. Then if that doesn't work check your filter and coil themselves. Your bike what is the miles and has it sat.
    Ride Safe
    Joe.
     
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  11. sprintdave

    sprintdave Nurse,he's out of bed again

    May 25, 2014
    1,495
    750
    Birmingham
    When was it last ok? Have you done anything at all to the bike since last used?
    If it is a new bike to you it may have flooded and fouled the plugs. New plugs in and don't touch the throttle when you try to start it as this floods the engine. Try with and without choke as it could be sticking. Check it is sparking coz it could be electrical issue.
    Don't try to start it with a low battery as it will shag the sprag clutch which is an expensive job. Fully charge battery and try again. Post back here and the boys will sort you out.
    Were valves done at 12000 miles as ut may be a tight valve?
     
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  12. GypsySOHMC

    GypsySOHMC Member

    Mar 18, 2019
    8
    8
    Stoke on Trent
    18,000 Miles it's sat for a few weeks. Plugs are new and I have gapped them, checked they have have decent spark. I've checked the plug leads and the coils.
     
  13. GypsySOHMC

    GypsySOHMC Member

    Mar 18, 2019
    8
    8
    Stoke on Trent
    18,000 Miles it's sat for a few weeks. Plugs are new and I have gapped them, checked they have have decent spark. I've checked the plug leads and the coils.
     
  14. GypsySOHMC

    GypsySOHMC Member

    Mar 18, 2019
    8
    8
    Stoke on Trent
    Bought it after 12000 miles
    Battery is new and fully charged
    sidestand switch cleaned
    clutch switch replaced
    Wiring connectors stripped and cleaned
    coils checked
    ht leads checked
    plugs new and gapped and have spark
    carbs stripped and cleaned
    fresh fuel
    and nothing at all
     
  15. sprintdave

    sprintdave Nurse,he's out of bed again

    May 25, 2014
    1,495
    750
    Birmingham
    Carb vacuum blocked, try on prime if you have that position on your bike. I have a Sprint so may be different. Remember to turn it back after tho. If the engine turns over it won't be the clutch or side stand switch.
     
  16. Sprinter

    Sprinter Kinigit

    Aug 17, 2014
    6,026
    1,000
    uk
    Starting System Symptoms:

    Weak battery symptoms:
    -- Slow cranking.
    -- Stops cranking suddenly on compression stroke with button pressed.
    -- Starts when starter button is released at end of cranking.
    Repair:
    -- Charge/Test/Replace battery.
    Failure Modes:
    -- Loss of capacity. Appears to charge, voltage good but no reserve for starting.
    -- Won't hold a charge.
    -- Low voltage/cell failure.
    Preventative Maintenance:
    -- Check fluid levels regularly
    -- Maintain full charge: Regular riding, trickle charger.

    Ignition Coil failure symptoms:
    -- Hard starting/misfiring during cranking.
    -- Rough idle that can't be tuned out with carb adjustments and carb cleaning.
    -- Idle misfire clears with new sparkplugs, returns in a few hundred miles
    Repair:
    -- Replace: Preferably with Nology for higher reliability than stock Gill coils.
    Failure Mode:
    -- Shorted turns in secondary resulting in weak spark.
    Preventative Maintenance:
    -- None
    Testing:

    Pickup Coil failure symptoms:
    -- No spark at all
    -- Spark quits with engine hot, returns when engine cool.
    -- Note: Pickup coil failure is total. There is no random misfire spark loss.
    Repair:
    -- Replace pickup coil
    Failure mode:
    -- Thermal intermittant with long (15-30 minute) period.
    Preventative Maintenance:
    -- None. Get a spare.
    Testing:
    -- Ohms checks hot and cold.

    Worn starter symptoms:
    -- Sometimes won't crank until the bike is rocked in gear.
    -- Excessively noisy cranking with a grinding sound.
    -- Click from under seat but no cranking.
    Failure Mode:
    -- Brush wear progressing to commutator damage.
    -- Bearing failure related to brush wear.
    Repair:
    -- Rebuild or replace.
    Preventative Maintenance:
    -- Maintain battery in peak condition.
    -- Follow proper starting procedures. Neutral, clutch in.
    -- Crank 5-10 seconds at a time max., switch off for twice as long before cranking again.

    Worn sprag clutch symptoms:
    -- Very loud rattling when cranking
    -- Starter spins but engine doesn't turn
    Falure Mode:
    -- Breakage
    Repair:
    -- Replace sprag clutch
    Preventative Maintenance:
    -- Maintain battery in peak condition.
    -- Follow proper starting procedures. Neutral, clutch in.

    Worn starter solenoid:
    -- Click from under seat but no cranking.
    -- Won't crank after rocking bike.
    -- Starter continues to run after bike starts and won't stop until the battery is disconnected.
    Failure mode:
    -- Internal contact damage resulting in non-conduction.
    -- Internal contact damage resulting in contacts welding shut.
    -- Internal damage/wear prevents solenoid core movement.
    Preventative Maintenance:
    -- None.
    Repair:
    -- Replace starter solenoid.
    Testing:
    -- For no cranking, short across solenoid high-power terminals. Normal operation denotes failed solenoid contacts.
     
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