raising revs, kills the engine!!!

[Seana23]

ok everyone, i hope your all well...
Ok, so ive had the bike (GS850GZ) totally rewired, ive compleatly cleaned the carbs and checked the CV diaphrams etc...
BUT...
the bike ticks over quite well but when i increase the revs the engine "chokes" and dies........
cant get the revs over about (No rev counter) 3000 rpm.

AAAaaahhhh!!!
what could be wrong?
new Boyer-Branson Ignitor box
(points set correctly)
new Ignition coils
new wiring
new battery

WTF!!
Help!
any ideas?

Seana
XXX

[pete]

Is your timing set right? When I was stuffing around with trying to get some GM style HEI modules to work it ended up being around 90 degrees retarded and revving would make it die out.

Check to make sure the rotor on the crankshaft is oriented the right way... not sure what's right for an 850 but it sounds like similar symptoms...

Of course I could be way off too but worth a check I reckon...

[Nessism]

Is the airbox installed?

[razor02097]

Is the airbox installed?

This is what I was about to ask...

[Big T]

WTF!!
Help!
any ideas?

Seana
XXX

As above, needs the airbox. If you're doing pods, time to start rejetting

[bwringer]

Is the airbox installed?

This is what I was about to ask...

As above, needs the airbox. If you're doing pods, time to start rejetting

Fourthed. Needs an airbox.

[hampshirehog]

new Boyer-Branson Ignitor box
(points set correctly)

Seana, you shouldn't have any points on there if you've fitted a new Boyer Bransden system.

Still - if it runs it's almost certainly not ignition related. My guess would be................................................ ..................



you need to fit the airbox. Sorry to be so predictable!

[Steve]

I agree with the airbox suggestion.

If you have your airbox off and want quick verification that that is all your problem is, try this:
Take a shop rag, fold it in half, drape it over the carb intakes. Use clamps or zip-ties to hold it to the outer carbs, keep it taut over the inner carbs. Your bike should now run somewhat "normally". It will be good enough for a trip around the block, but will not be accurate enough for any jetting checks.

.

[Seana23]

ok thanx all. No i have no airfilters fitted at the mo... when they are, they are K&N's...
i'll try the rag thang.
i'll check the Ignition advance (Not points-set, sorry)

and i'll check the main jets... think they are 150's so cant imaging that they need to be bigger, but m\ybe ive gone up a bit too far...

ok, i'll get my fingerless gloves on and get back out there and check a few things and get back to you all.

thanx again for all your help.
XXXXXX
Seana
XXXXXXX

[verde]

and i'll check the main jets... think they are 150's so cant imaging that they need to be bigger, but m\ybe ive gone up a bit too far...

Yeah, if you go too far over on the main the bike will feel like it bogs and falls flat on it's face. The rag trick will verify if this is the problem as it will worsen it

[pete]

Is your timing set right? When I was stuffing around with trying to get some GM style HEI modules to work it ended up being around 90 degrees retarded and revving would make it die out.

Check to make sure the rotor on the crankshaft is oriented the right way... not sure what's right for an 850 but it sounds like similar symptoms...

Of course I could be way off too but worth a check I reckon...

I should really learn to stop before I type

Apart from the fact I was way wrong I should've said 180 degrees not 90 degrees...

[Seana23]

thanx Pete. nope, timing is set fine. i'm gona take the carbs apart one more time and reinstall the original jets and stick the air-filters back on and see if that makes it run better.

thanx all.
I'll get back to you all.
XXXX

[pete]

thanx Pete. nope, timing is set fine. i'm gona take the carbs apart one more time and reinstall the original jets and stick the air-filters back on and see if that makes it run better.

thanx all.
I'll get back to you all.
XXXX

haha all good Seana, and I reckon if you follow everyone else's advice (not mine) you'll be right

[koolaid_kid]

Seana, while going back to stock and starting over is not a bad idea, you may want to install the K&Ns first with the current jets to see what that does for you. Just a suggestion.