Hi all, question from new owner

[Mark II]

So I just purchased a 1993 Tiger and it has an issue I would like to solve.  When I let off the clutch to accelerate, there is a gunshot-like backfire.  Former owner said he hasn't ridden it much in the past four years or so (4,000km in that time), and hardly at all for the past 4-6 weeks.  How can I fix the backfiring issue?

[Mustang]

you didn' give much to go on for a description of problems or how many miles are on the bike total , but I would wager that the intake valves have zero clearance and is in need of an adjustment .

CHECK YOUR VALVE CLEARANCES

[Mark II]

75,000km total as of now.

Paperwork says the top end was rebuilt at 71,000km which was 4 years ago.

[JetdocX]

Timing incorrect?  Check the cam chain timing.  You are going there anyways to check valve clearances. :D

[Mustang]

Timing incorrect?  Check the cam chain timing.  You are going there anyways to check valve clearances. :D

could well be timing is off seeing how the top end was 'rebuilt 4 years ago' . That would be about the time previous owner quit riding it or chain has stretched causing bad timing
and 1 other thing .......could be a knackered ignition coil
I've seen this scenario before :
1 cylinder not firing and when the rpm comes up, bang when the unburned fuel ignites and the coil starts firing again above 4500 rpm

Start with the valve clearances .they should be .10-.15 mm for the intakes and .15-.20 mm for the exhausts . while you have the valve cover off confirm that the timing marks line up . If you found some intake valves that have zero clearance , you found your problem ,  Now if everything checked out ok( good clearance and proper timing ) move onto the coils they should ohm out at .6  ohms across the + and - terminal if you have all three check ok that does not mean that they are all good cuz I have seen them ohm out good but still cause misfires , especially if you have Gill coils instead of PVL's .
 feel the pipes at idle on freshl;y started motor if 1 of them is cold to touch you have a bad coil on that cyl .

If you are 100 % positive that your coils are good , move onto the carbs next

If you don't have a repair manual I suggest either getting the factory bible or a Haynes manual
somewhere in that mix you will find your problem

compression , spark , fuel  check it in the order I listed

[JetdocX]

Oh, and get used to taking this bike apart.  You will do a lot of this.

[Mark II]

Update: turned out to be the O-rings on the carbs.  Coils were fine.  It is still running rough, but I attribute that to a leaking fuel tap not allowing a proper flow.  The search for parts continues....

It's a good thing I invested in a low-maintenance bike! :roll: