Thunderbird 1995 - Starting Cold Issues

[Grim1965]

Hi Everybody
I have recently bought myself a lovely Thunderbird 900 Mikuni Triple which I am absolutely loving - however I am having issues starting from cold. Once started it runs well but doesn’t like choke at all & will not start with choke & if it does fire will stall immediately once manual choke is applied.
The battery is very strong & turns it over very easily & it sounds like it really wants to start but struggles. It typically takes about 10 -12 goes before it will fire & you have to add minimum revs just to try & help the engine pick up...once warmed it starts easy every time.
The previous owner hadn’t ridden it much in a while & said he had put a carb kit through it approx. 12 months earlier. I have added a new air filter, new plugs, cleaned the carbies - reset the mixture screws to handbook settings & for good measure changed the engine oil...but I still have the same starting issues...VERY Frustrating!!
On trying all kinds of permutations I have found that if I wind in the idle screw a couple of turns from its normal idle position (1000-1050 rpm) it will start somewhat easier typically 2 attempts.
Can anybody shed any light on what my issue may be & what I can possibly try/do to rectify this? I would love to just walk up to the beast – pull the choke lever turn the key & hear it fire first time…Heaven!!

 

[shanered6]

Hi there , it sounds like is is running rich and could be a number of things , but you say you've cleaned and reset carbs ... did you reset your float levels ? also you say the previous owner put a carb kit through it ... what kit ? and how many miles has your bike done ?

 

[Grim1965]

Hi there , it sounds like is is running rich and could be a number of things , but you say you've cleaned and reset carbs ... did you reset your float levels ? also you say the previous owner put a carb kit through it ... what kit ? and how many miles has your bike done ?

Hi Shane
I am led to believe it was mainly gaskets and seals were renewed in the carbs.
The bike is in well maintained condition generally & has approximately 80,000kms

 

[shanered6]

Ok , two things 1) with 80,000kms its probably a fair bet the idle jets are worn which will make it run very rich on tick over , 2) the other thing is hopfully he fitted the right gasket set as the thickness of them is critical for fuel level in the bowls .

 

[Grim1965]

Ok , two things 1) with 80,000kms its probably a fair bet the idle jets are worn which will make it run very rich on tick over , 2) the other thing is hopfully he fitted the right gasket set as the thickness of them is critical for fuel level in the bowls .

Thanks Shanered6
Looks like I should get a new gasket kit & idle jets & start there and see what develops from there!
Do you know the part no for the correct kit/jets?

 

[shanered6]

Im sorry on the part numbers i dont know but im sure you should be able to track them down .. try World of Triumph and go to spares and accessories , and if it were me i would buy a complete jets and gasket kit and try going straight to Mikuni if you get no joy from Triumph .

 

[B25bsaboy]

Before you start tearing the carbs apart, add some sea Foam to your fuel and burn a tank of fuel. If the carburetors are gummed up, this will clean it internally.
Also may want to check your coils, as I had the same issue and converted them to stick coils from the coil packs that the Triumph TBird 900 came with.
On a side note, I have had five (5) Thunderbirds and the last one I bought came with a seized engine as the Sprag Clutch failed. Stripped the engine down, replaced it and the engine now has the updated Triumph Sprag Clutch assembly. Your TBird looks identical to mine and I will say you can make Suttle changes to the TBird and you will be happy. Of the five (5) TBirds I have owned, I like the 1995 (original) that I now have.