fuel starvation under load (a lttle history)

[PaulG]

hi - its been since last june '10 that i posted re my leaking carbs

my carbs are now leak free - i found some real mechanics over the winter this time at www.motorcyclecityinc.ca - they are located in Richmond Hill north of Toronto and do work mostly on older machines (also a Hyosung dealer) - if you are stumped they can probably fix it at a fair price and they won't BS you

they cleaned them - tested them - and wow they didn't leak, hmmmmm - they also found that my crankcase filled up with gas while i was dickin' around with it - total cost was only about $340 including cleaning out the engine - a fair deal considering those f*****s at that other Yamaha dealership...  (if i say any more would i get sued?) hosed me for over $600 and gave it back to me still leaking (they just lost a potential Super Tenere sale the idiots) - anyway i digress, sorry

like i said the carbs don't leak but...

they never had a chance to take it for a test ride before i picked it up (crappy spring) - the bike ran ok under normal load, but when i gun the throttle to merge onto the freeway or pass it bogs down even at city speeds - i can run it ok at normal acceleration up to about 5000 rpm - but after that it also starts to sputter especially if i start going up grades

i changed the fuel filter, air filter (it was fouled when some oil/gas got down into the air box), fuel pump works ok,  but no improvement

my Clymer manual troubleshooting guide suggests if all the fuel systems are functioning, then it may be electrical due to faulty coils, pickup coil, or ignitor unit - i doubt that's the case (or hope it isn't)

the mechanic suggested running a few tanks of premium (i used 94 octane) to see if it helps get rid of the old gas and additives - i've gone through two tanks with no improvement - if that doesn't work then back to the shop it goes

i don't hold them responsible for this as i had no idea this was an issue, since the problem was originally leaking carbs, and the bike never ran until they fixed it which finally exposed this issue - i don't mind taking it back to them again since my facilities are sparse (my driveway) and i know they will get it fixed

just wondering (after all this  ) if anyone has had a similar issue and how it was fixed - maybe i could get it done myself even with my ten thumbs

sorry for being longwinded - thought a bit of background may help - makes up for not posting for a year   

[Harvy]

Hi Paul...... couple of thoughts.
Did the shop change any carb internals? Is it sputtering because its getting too much fuel, or not enough spark?
I had similar issues and over time determined that I had both problems.
I knew mine was running rich, so ended up replacing main jets, needles and more importantly - emulsion tubes.
That fixed up the rich issue.
I then had a similar issue as you at around 6000rpm....... the engine would run strongly to there and then fart and carry on like an old mole at a christening. I replaced plugs, and plug leads......still no better. Anyway, to cut a long story short, a Dyna2000 system, Dyna coils and plug leads and she's as good as new.
I know this was overkill, and I should have tried new coils first, then probably the ignition module, but I found the Dyna stuff cheap, so went the whole hog.

Harvy

[grannyknot]

Paul, that Yami dealership wouldnt happen to be Yamaha of Newmarket would it?

[PaulG]

gadzooks - curiouser and curiouser said alice - thanks for the info

just a couple of Q's

is this the Dyna kit you were talking about?

http://cgi.ebay.ca/DYNATEK-DDK7-1-DYNA-2000-YAMAHA-FJ1100-FJ1200-IGNITION-/260757438410?pt=Motorcycles_Parts_Accessories&hash=item3cb65abfca

or this one?

http://cgi.ebay.ca/Dynatek-4000-Crank-Trigger-Ignition-Yamaha-FJ1200-FJ-/400222544699?pt=Motorcycles_Parts_Accessories&hash=item5d2f1f633b

coils?

http://cgi.ebay.ca/Dynatek-Ignition-Coil-Kit-Yamaha-2-2-ohms-DC4-1-CDI-/140563889016?pt=Motorcycles_Parts_Accessories&hash=item20ba42bb78

i guess if i choose this route i could start with the plug leads - everything is still original as far as i know so after 19 yrs a little change might be good for the ol' gal

i'll check the "parts for sale" like you did (you can't hide from google), maybe get lucky

[PaulG]

oh yeah

the Yammie dealer is the one in Scarborough - thats as far as my legal dept. said i could go   

[Harvy]

Yes Paul......the first link is the correct kit. The coils are not however. And I got my whole setup for around $50 less than that mob is asking for just the pickup-plate and module.

From memory US$246........ I think I must have just got lucky or something...... Was from a mob called BadBoyz in Ca.

Harvy

[SlowOldGuy]

I kind of like the size of those coils. 
The mounting slots might be easier to work with.
IIRC, the grey coils are 2.2 ohms so they should work well with a Dyna system.

davidR.

[Harvy]

I kind of like the size of those coils. 
The mounting slots might be easier to work with.
IIRC, the grey coils are 2.2 ohms so they should work well with a Dyna system.

davidR.

Agree with you on the 2.2 Ohm David, and the size does look a little smaller, so they may fit a little better, but it seems to me the HT horns at one end and the wiring terminals at the other would put one or other into the oncoming weather (meaning rain). At least with the older grey coils the electrical connections are at the back out of the weather. Not my $118 to play with so s'pose I should shut up.
Seems I got a bloody good deal on mine......I see the mob I got em from are charging a lot more now.

AS for mounting the older style grey coils. I used all the original mounting hardware, and found that if you ditch the 2 square plastic pieces that go into the square holes, they fit pretty snug in the OEM position. The only other thing I had to do was grind the rivet off for the thru bolt at the back..... this does not affect the coils as there is a second rivet closer to the coil body.


Harvy

[PaulG]

looks like you got a great deal at $246 USD

ebay is around $460 plus shipping for a complete kit with CDI, wires and coils or $300 just for the CDI

i found a Dynatek distributor about 20 min from my place, so i'll see what they have available - who knows maybe pigs fly