FXR misfire?

[bigreddog]

Lewis's FXR is misfiring after 1 or 2 laps, did it at levels yesterday, actually stopped at one point.
Re-starts fine....

Link here to a wee vid of it doing at levels yesterday...

http://www.youtube.com/watch?v=8efdt1OjnHM

Initially thought of carburation or fuel blockage because I cleared a lot of crap out of the fuel tap and tank the other day.
Tried the RG tank on it yesterday and it was the same.

Now leaning towards electrical issue CDI,Coil etc....

Any ideas Guys???????????

[Henk]

Check the plug for the CDI, they have a tendency for crap connections. I've zip tied mine on now.

[mr bucketracer]

could be a to smaller engine breather or a buggered battery as bert found out

[SVboy]

Check the plug for the CDI, they have a tendency for crap connections. I've zip tied mine on now.

Is that my old bike? If so, a wire in the above mentioned plug came loose at one stage-check that that has not happened again?

[bigreddog]

Is that my old bike? If so, a wire in the above mentioned plug came loose at one stage-check that that has not happened again?

No not that one chris... im using that and its running great.:niceone:

[bigreddog]

could be a to smaller engine breather or a buggered battery as bert found out

Not running battery as starter motor removed etc...Engine breather if of sufficient size.
Thanks for your thoughts tho..

[mr bucketracer]

if its a oko carb it prombly be the floats sticking and running out of fuel

[bigreddog]

Check the plug for the CDI, they have a tendency for crap connections. I've zip tied mine on now.

Have zip tied CDI to frame now as it was flapping about a bit....will zip tie connector on as you suggest..

[bigreddog]

if its a oko carb it prombly be the floats sticking and running out of fuel

No its a GN 250 carb,think there a 28mm Mikuni CV by memory,have checked float height and operation,seems OK.

Are OKOs prone to the floats sticking a bit ?...Have one of those and was planning on changing the GN one for it..

[mr bucketracer]

No its a GN 250 carb,think there a 28mm Mikuni CV by memory,have checked float height and operation,seems OK.

Are OKOs prone to the floats sticking a bit ?...Have one of those and was planning on changing the GN one for it..yes , the first thing is bend the floats out , apart from that they are a real easy carb to set up

[bigreddog]

yes , the first thing is bend the floats out , apart from that they are a real easy carb to set up

Are you running an OKO 28mm on an FXR?
If so what main jet size did you use?

[Bert]

Not running battery as starter motor removed etc...Engine breather if of sufficient size.
Thanks for your thoughts tho..

If that's the case then likely a coil breaking down under load.

Can I suggest that you put a battery back on it and see if it runs correctly.

Also check your spark plug cap, mine was a complete mungrel surprised it ever had sparked.

[mr bucketracer]

Are you running an OKO 28mm on an FXR?
If so what main jet size did you use?i have a 30mm but no much in it ..how hot is the motor? 1.12 to 1.18 is about right and drop the needle down 1 from middle .. a good base point

[bigreddog]

If that's the case then likely a coil breaking down under load.

Can I suggest that you put a battery back on it and see if it runs correctly.

Also check your spark plug cap, mine was a complete mungrel surprised it ever had sparked.

I'm with you on the coil idea,but wonder why it is OK for a while?

Battery idea I had thought of but then I remembered that it had done it before I took the battery off!!!!

Will change plug cap as you suggest....

[bigreddog]

i have a 30mm but no much in it ..how hot is the motor? 1.12 to 1.18 is about right and drop the needle down 1 from middle .. a good base point

Motor is flowed head,2mm O/S piston,GN carb,no starter etc

Standard Cams...

The 28mm OKO I have got hold of is missing the needle, clip, spring and plastic spring holder,Do you know of anyone in NZ with these bits?

[Bert]

Motor is flowed head,2mm O/S piston,GN carb,no starter etc

Standard Cams...

The 28mm OKO I have got hold of is missing the needle, clip, spring and plastic spring holder,Do you know of anyone in NZ with these bits?

Yip. Pm me your address...

:psst:I think you have a cam problem.... You need the GPR racer grind :msn-wink:

[hal20308]

Not running battery as starter motor removed etc...Engine breather if of sufficient size.
Thanks for your thoughts tho..

Had a similar problem after a fresh FXR install into a TZR frame in testing at Kaitoke a couple of weeks ago - various parts sourced from bike breakers and we had a duff reg/rec. Dependent on you have wired it up, you should be able to put a good fully charged battery in and disconnect the reg/rec so your are running total-loss. That will tell you whether the reg/rec is OK or not and also whether the stator output is clean...............Suzuki have never had the best electrics out of the main Jap manufacturers in my experience.

[bigreddog]

Had a similar problem after a fresh FXR install into a TZR frame in testing at Kaitoke a couple of weeks ago - various parts sourced from bike breakers and we had a duff reg/rec. Dependent on you have wired it up, you should be able to put a good fully charged battery in and disconnect the reg/rec so your are running total-loss. That will tell you whether the reg/rec is OK or not and also whether the stator output is clean...............Suzuki have never had the best electrics out of the main Jap manufacturers in my experience.

many thanks for your ideas, I will re-fit battery
Def right re Suzuki electrics..

[F5 Dave]

I'm waiting for a $10 generic regulator to arrive which will probably be sufficient for the job and likely the same almost tolerable quality, but new.

[bigreddog]

I'm waiting for a $10 generic regulator to arrive which will probably be sufficient for the job and likely the same almost tolerable quality, but new.

where can I get one of those dave?

[F5 Dave]

Dealer extreme. Google it
Lots of crap from China.com but with some good stuff. I haven't seen one of these yet but I'm not putting much stress on system.

[John_H]

Dealer extreme. Google it
Lots of crap from China.com but with some good stuff. I haven't seen one of these yet but I'm not putting much stress on system.

Do you mean deal extreme aka dx.com?

[timg]

Sounds like the symptoms I had on my old FXR when the regulator/rectifier failed. Went as per normal for a couple of laps and then started missing. Cooled down and went fine again only to start missing again after a few laps. Went total loss after that. FXR happily does a couple of days back to back on a good battery (cos I forgot to charge between meetings) :facepalm: Cheers

[bigreddog]

Sounds like the symptoms I had on my old FXR when the regulator/rectifier failed. Went as per normal for a couple of laps and then started missing. Cooled down and went fine again only to start missing again after a few laps. Went total loss after that. FXR happily does a couple of days back to back on a good battery (cos I forgot to charge between meetings) :facepalm: Cheers

Yes Tim I reckon that if re-installing battery doesn't work, I'll try reg/rect
PS: Did you end up with a spare front guard for FXR?

[timg]

Yes Tim I reckon that if re-installing battery doesn't work, I'll try reg/rect
PS: Did you end up with a spare front guard for FXR? No, no spare front guards sorry.

[F5 Dave]

. . . on a good battery (cos I forgot to charge between meetings) :facepalm: Cheers

Funny I was just having that conversation before logging in as my reg/rec arrived on my desk.


Seen many people's race meet spoiled due to a battery failing/ forgot to charge/still on the charger at home/ any combination of above.

I vowed from that day(s) my bikes would be push & go.

Nothing to report on this one as it looks like a rec/reg, and yes CYT brand on DX, cost $10 landed. It says Super Wear Resistant. Sounds good. I hate it when my electrical products wear.

[Bert]

Funny I was just having that conversation before logging in as my reg/rec arrived on my desk.

Seen many people's race meet spoiled due to a battery failing/ forgot to charge/still on the charger at home/ any combination of above.
I vowed from that day(s) my bikes would be push & go.


While I agree somewhat (given I've had issues with failing batteries) I've also lost many days with stuffed charging circuts...

You can't win, one can only put ones best foot forward and have a system that you feel you have the most control over...

[bigreddog]

Finally some time to check FXR out with battery re-installed....

Ran it today with no problems for about 20k's....a lot of it flat out.

So battery has solved the problem?...I still don't understand how the battery has had this effect.
Can someone pls enlighten me.

Just to re-cap bike has starter and associated gears removed and no instruments.

[Henk]

Sounds like maybe your stator has crapped out and isn't giving enough grunt at higher revs. They will run without all the stuff you listed just fine. I have the stators on all our buckets because I don't trust myself to charge batteries enough to run total loss. Time to fire it up with a multimeter and check the charging circuit, 20ks isn't enough to flatten the battery enough to have it running badly if the charging circuit is toast.

[Pumba]

.......20ks isn't enough to flatten the battery enough to have it running badly if the charging circuit is toast.

No that takes just under a week of Auckland commuting on a Triumph Speed Triple before you are pushing it down Great South Rd. You might get a bit more out of the FXR.

[bigreddog]

Sounds like maybe your stator has crapped out and isn't giving enough grunt at higher revs. They will run without all the stuff you listed just fine. I have the stators on all our buckets because I don't trust myself to charge batteries enough to run total loss. Time to fire it up with a multimeter and check the charging circuit, 20ks isn't enough to flatten the battery enough to have it running badly if the charging circuit is toast.

forgive my ignorance Henk, But am I correct in thinking that the battery is making up for a slightly dodgy charge at high revs?

[mr bucketracer]

forgive my ignorance Henk, But am I correct in thinking that the battery is making up for a slightly dodgy charge at high revs?thats what he is saying , cheak with a meter if charging ..over 14volts just ticking away

[Henk]

thats what he is saying , cheak with a meter if charging ..over 14volts just ticking away

Yep that's it. Stick a meter on there, start it up and check the battery voltage. It should be around 12 without the engine running and up around 14.4 when the revs come up.

[bigreddog]

checked today and bike is charging fine, have taken stator cover off and checked everything in there... seems good

might just convert to total loss and have done with it...

[bigreddog]

checked today and bike is charging fine, have taken stator cover off and checked everything in there... seems good

might just convert to total loss and have done with it...

latest instalment is that I tried another carb (gn 250 cv swapped for 28mm oko) bike ran fine for 2 x 15min sessions at levels
on Friday...

[F5 Dave]

Where did I read that 90% of ign problems end up being carb related and vice versa:lol:

[bigreddog]

Where did I read that 90% of ign problems end up being carb related and vice versa:lol:

reckon youre right there dave....

[bigreddog]

bike completed 4 races at Ruapuna today with its oko carb...all good,except carb needs fine tuning
so I reckon we'll put this one to bed and put it down to the gn250 carb malfunctioning somewhere along the line

never mind I learnt quite a bit going through this process