97 VTR250 backfiring?

[dangerous]

Ok... heres a curley one,
'True-to-Life' has brought her 1st road bike and is loving it to bits, now I went over the bike befor she brought it and it came up reasonble clean.

Now today I followed her through the hills and on deaceleration down hill only (dosent do it on the flat) and the bike would back fire in a serious manner, smoke/flame sort a thing.

Now I am yet to do a compreasion test and it hauls good arse, does not miss or stutter at all, seems to have all its power there.

This back fire is not a good thing... what you motley lot out there reckon it could be?

[NighthawkNZ]

I would take a closer look at the muffler... for a start

[JimO]

my boys 97 vt250 backfires going down hill as well

[NighthawkNZ]

my boys 97 vt250 backfires going down hill as well


pretty sure Xaria's doesn't... hmmmm

[dangerous]

my boys 97 vt250 backfires going down hill as well
loud as a gun shot? fire out the tail pipe?



I would take a closer look at the muffler... for a start
for air leaks?
I did a quick look over all the exhaust system and all seems well

[NighthawkNZ]

for air leaks?
I did a quick look over all the exhaust system and all seems well

Yeah air leaks... maybe a closer look at the baffles... header pipes for leaks...

The other thing I would check would be timing?

FROM WIKI http://en.wikipedia.org/wiki/Back-fire
Common causes of backfires are:


Timing – If car is distributor (http://en.wikipedia.org/wiki/Distributor)-less
Timing – If a two stroke engine (http://en.wikipedia.org/wiki/Two_stroke_engine) is backfiring every other stroke.
Fuel pressure (http://en.wikipedia.org/w/index.php?title=Fuel_pressure&action=edit&redlink=1), fuel filter (http://en.wikipedia.org/wiki/Fuel_filter) and pump (http://en.wikipedia.org/wiki/Fuel_pump) – leaks and corrosion (http://en.wikipedia.org/wiki/Corrosion) could cause lack of fuel during the fuel injection (http://en.wikipedia.org/wiki/Fuel_injection) event.
Bad wiring (http://en.wikipedia.org/wiki/Electrical_wiring) in ignition (http://en.wikipedia.org/wiki/Ignition_system) – ..if car (http://en.wikipedia.org/wiki/Automobile) won't run for more than a few moments.



I just asked Xaria and she say's no never heard hers back fire before.

[JimO]

loud as a gun shot? fire out the tail pipe?



for air leaks?
I did a quick look over all the exhaust system and all seems well

no more of a loudish ( loud but not to loud) popping noise

[JimO]

pretty sure Xaria's doesn't... hmmmm

if i was you i would go back to where i got it and complain

[true-to-life]

COMPLAIN! I'm a woman, who ever heard of us doing such a thing? Besides, it's a private sale, I bought her as is, And I love her. NighthawkNZ thanks for your post.

[dangerous]

COMPLAIN! I'm a woman, who ever heard of us doing such a thing? Besides, it's a private sale, I bought her as is, And I love her. NighthawkNZ thanks for your post.

haha... na hes meaning NHNZ re: A's bike not back firing, LOL you will get how it works around here soon enough.:scooter:

[NighthawkNZ]

if i was you i would go back to where i got it and complain

backfiring... adds a bit of character huh? :lol:

[Squiggles]

Check the rear header pipes for a leak

[007XX]

COMPLAIN! I'm a woman, who ever heard of us doing such a thing? Besides, it's a private sale, I bought her as is, And I love her. NighthawkNZ thanks for your post.

Congrats on your purchase...I got the same one as well (same year), and I absolutely :love: her too...Have decided against trading her for anything else for quite some time, much to the disappointment of my mates who want me to get something bigger.

Anyway, mine never backfires unless I ask her to :D...by hitting the killswitch and then starting her up again, preferably when hubby is riding alongside so I can scare the bejesus out of him :lol:

I've never noticed a problem in the sound she makes when going downhill, but the exhaust system has been modified prior to me buying her, by installing a twin carbon pipe system which really "opens her up"...maybe this helps, I'm not sure.

Anyway, good luck with it and hope you find the problem.