1996 250 hornet Backfire issue

[Newkid]

hey guys, have read through the forums to see if i could find a thread relevant to this and the closest one i could find was the Hyu backfiring.. seemed the bikes would be completely diff so thought i would start a thread asking for advice.

I picked up the bike on monday after having it in for an Oil and filter change, new tyres, and new brakes + Bleeding of lines. When picking it up from the shop it was a real pig to start. Once going and slightly warm every single gear change it would bang like a shot gun going off, also on decel it would backfire like mad. this morning again it was a pig to start, had the choke out, gave it little bits of throttle and with a loud bang at 6am it started. Then ran fine the hole way into wellington from Aotea. What would be common causes for this to happen? the bikes been a dream to ride and use up until the service. Where should i start looking to see if i can rectify the problem? I wont know until i go back out tonight after work to see if it does the same thing but im assuming it will. Bike is always garaged and well maintaned so im very stumped.

Cheers Newkid

[Slyer]

Did you ask the dealer?
Does it have any other issues like erratic idling or poor acceleration at high rpm?

[Newkid]

I did ask the guy why it was so hard to start, and also why it had started back firing since leaving his workshop. he said they didnt touch anything that would cause that only did what was asked, the oil filter etc. It still has great overall power for a 250. its not missing, just backfiring

[imw-hornet]

Once it has started ,,, is there a strong smell of gas ,,, maybe get carbs cleaned and checked , also maybe a good idea to check the plugs , hope this helps , Cheers

[Neon]

If you are certain it was running sweet before the service was done then you need to insist that the mechanic look at it again. Just because they say they 'have not touched anything that could cause the problem' doesn't mean anything. Don't let them fob you off

Something similar happened at my last service - I insisted that it was their doing and it turned out they had made a balls up, after trying to convince me that the problem was my riding. Dicks.

[DarkLord]

Do what I did with mine - put the bike in neutral, let it idle and run your hand around the header pipes to see if you can feel any air leaks due to cracks/holes in the headers. If so, there is a good chance that is your problem.

If that is the case, how they could have got there is anyones guess. I still don't know how mine got cracked.

[joshy28]

F@#$ that!!!!. Take it back and insist strongly that they ARE going to fix it...