2 steps forward... 2 steps back...

[Barnfresh]

So I thought I would do some good things to Bagapotomus last week...
A new set of NGK plugs and switched to Mobile1 20w-50. Very proud of myself.
So out for a ride and I get a high speed miss... then a low speed miss.. and then the starter starts to disengage while it's cranking. It cranks - then jumps out and spins - the re-engages. I afraid I'm going to tear up the starter drive.
So a new set of AC plugs and the miss is gone but I'm not sure about the starter. I read that thicker synthetic oil can cause the starter drive to not engage?
So now I have to go back to thinner dino oil? All my hard work and trying to impove things was for naught? !!!!

[TopCatGr58]

Hey there,

Sounds like you didn't do enough re-Searching of the threads before jumping to Mobil 1 FULL SYNTH! It's not so much the thickness at these temps, but just the slipperyness of the synth vs. DINO! Dino 20-50 is what is recommended for these engines, especially for environmental temps above ~50 degrees! So...yes, changing back to DINO...brand of your choice without Friction Modifyers noted on the SAE/API seal in 20-50 flavor should be just fine. Run a few ounces of MMO or Berrymans/Sea Foam and such in the oil for a few minutes at IDLE(No LOAD, NO WOT REVVING) before draining can help flush out the SYNTH better, operate the clutches as well...surprised you didn't report clutch slippage as well with the SYNTH, but perhaps you just didn't get to ride it enough to experience that side affect as well!

As to the plugs and miss, many folks swear by NGK...I use AC myself, you may have just gotten a bad plug.....did you test the pipes with water to see if you had an actual cooler pipe, or just a high speed miss??

Sorry you spent/wasted the $$ on the Synth oil!

T.C.

[Barnfresh]

Thanks TC... I should have known from the picture on the bottle!

[Barnfresh]

I wanted to get it running today and do the clean and purge as TC suggests.. but did not want to strain or break the starter drive, so I got out the kickstart lever to give it a try - have not used it before on this bike.

The big four was surprisingly easy to start. It spit once with the choke all out and then hummed right into an idle with the choke off on the second kick. Seens like the spark may be hotter when not running the starter. Also, the gearing on the kicker must spin the engine through 1 cyl firing, maybe 2 -which is enough. I know the earlier frames had a holder under the battery box where the kick lever is stored? My '80 frame does not have that.

Too bad the kickstarter can't stay on - I'd use it all the time and save the starter / electrics. Intended for emergency use only I guess.
I think I saw a modified kick start lever that stays on the shaft and folds out of the way? Has anyone used that and if so, does it work ok?

[natemoen]

I think its the 750-850 kick start lever that has the pivoting head that can stay on.

[TomB]

I think I saw a modified kick start lever that stays on the shaft and folds out of the way? Has anyone used that and if so, does it work ok?

You can use XS750/850 Special folding kickstarters as they're cranked out to clear the exhaust but I think theres still an issue with hitting the footrest.

I've used an RD250/400 on my monoshocked XS11, its a straight lever but I have folding footrest and brake lever so no issue with clearance.

[Barnfresh]

Thanks Tom.. looking at the 850 to put it on and leave it on. I guess the 400, 750 & 850 all had the same size output shaft that it clamps on?

[WMarshy]

Yamaha ditched the kick start in '80 thats why you dont have a spot to store it. That also means you have a '78 or '79 engine with the kick start shaft... or you installed it..?

[Barnfresh]

Yamaha ditched the kick start in '80 thats why you dont have a spot to store it. That also means you have a '78 or '79 engine with the kick start shaft... or you installed it..?

Yeah.. I put in a used '78 engine when the original dropped a valve... I think they should have left the kickstarter on all of them. 1980 was all about emission control, non adjustable timing and slides... maybe saving weight by eliminating the kick starter? The 78 power curve has mucho more umph.