1980 WR 390 Rescue...

[justintendo]

Had that happen to me on a 1980 Suzuki GS 850 G back in 81! I had detailed the bike over the weekend and on the way to work Monday morning I cracked the throttle and almost slid off the seat... Last time I ever Armoralled a seat on a bike!

thats how it would have to happen on a 390 in 6th gear too...armor-all on the seat

 

[Bigbill]

I was standing up with the throttle cracked. I had to pull myself back up on the bike.

 

[SnoDrtRider]

thats how it would have to happen on a 390 in 6th gear too...armor-all on the seat

The thing about that is as you slide back you tend to twist the throttle a bit more! Luckily the Suzuki was a drive shaft bike and didn't like to wheelie!

 

[justintendo]

The thing about that is as you slide back you tend to twist the throttle a bit more! Luckily the Suzuki was a drive shaft bike and didn't like to wheelie!

strange but true...the shaft bikes all kinda rise a little when gassed. weird in the corners..

 

[oldbikedude]

Gyro effect

 

[Eric The Leg]

I was standing up with the throttle cracked. I had to pull myself back up on the bike.

Standing, in 6th gear? If I stood up while coasting after reaching 6th gear the wind would probably take me off the bike, no power needed.

 

[suprize]

Big bill has a gravity bonus (no offence intended Bill )

 

[Eric The Leg]

Big bill has a gravity bonus (no offence intended Bill )

I've got a pretty good gravity bonus myself...

 

[suprize]

always handy when: yachting, its windy, your first into the airliner seat

 

[SnoDrtRider]

First time in the light of day...

Took her for a little ride... way rich... I was following the needle setting from the factory... I guess someone screwed with the jetting. Seems I am missing a spacer in the carb also. It is # 29 in the parts manual showing the carb... a spacer that goes between the main jet and needle jet. I think that would put the main jet too close to the needle and cause a problem.

Video to follow...

 

[SnoDrtRider]

Received the new carb today... (gotta love Amazon)

I knew the jetting would be wrong so I planned on just swapping all my brass to the new body.
I looked using the search here and found a few suggestions as to what the jetting should be... Once I got my old carb apart I found out that the only thing that was close was the pilot jet (#40) and the main (440)
Slide was the correct 2.0 but I couldn't use it in the new body because the idle screw and guide slot are on the opposite sides on the new carb???
I figured I would just use the 2.5 that came with the carb.
My eyes are getting bad so the only way I could see the numbers was to take a picture and come blow them up on the computer... (Poor Mans Electron Microscope)
Anyway, the Needle jet is a Q-8??? and the needle ends in 3 or 5....
Whatever...

I decided to put together and install it and hope for the best... WOW I'm scared of this bike now! I didn't get a chance to run her at top end but low and midrange are clean and crisp just a little blip of the throttle and the front wheel is off the ground. It was getting dark so I didn't even get it out of second but I am happy!

Here are the parts... that were in the old carb that I switched to the new body. The part that I needed that was missing from the old carb is what I would call a jet carrier it holds the needle jet in and the main screws into it.

Here the cutaway on both slides is facing me...

Needle Jet...

The needle... Looks like a 5 to me...

 

[suprize]

not seeing the pics again...

 

[Eric The Leg]

Agreed, not seeing pics in the thread, but there is a direct link to the Google image gallery on page 5 of the thread, just sayin'.

 

[suprize]

riiight...ill go sneak a peek

 

[SnoDrtRider]

Just in from a few runs up and down the field and through the woods out back... She's a screamer! I still don't understand the jetting that's in there but I works that is for sure! Runs clean and crisp... too much throttle and she stands up proud!

Bike seems geared a bit too high in the tight sections but maybe I just need to get used to riding faster!

 

[Eric The Leg]

Just in from a few runs up and down the field and through the woods out back... She's a screamer! I still don't understand the jetting that's in there but I works that is for sure! Runs clean and crisp... too much throttle and she stands up proud!

Bike seems geared a bit too high in the tight sections but maybe I just need to get used to riding faster!

Every spring my WR feels like it's geared too high for about the first 15 minutes I've got it out. After that, it seems perfectly fine as long as I'm not riding with a slow-poke, or on a technical single track.

 

[suprize]

sounds like the needle is lean...drop the clip one spot and see how it goes. if it blubbs or drags as you open the throttle, it was right. if your too lean, it should smooth the transition out a bit and bring some lower power in a tad.

 

[jo360]

One thing i found with my ac 430 is that it takes quite a while to warm up properly, more than what you would expect for a fin job, also noted that decel from high speed in gear produces massive vacum that pulls too much air through the air screw circuit and leans out the mixture, i run a 50 pilot, 168 main with air screw at 3/4 .
Runs rich for first 15 mins then is good the amount of warm up required screwed my jetting initially.
This is a keihin 38mm but maybe other people have same experience regarding the warm up period.

 

[SnoDrtRider]

She was a bit loaded up in the first video...

OK I am about done with photos and video on this site... Tells me what I can embed then tells me it's not allowed.
when I do post pictures people can't see them.

 

[suprize]

I just select my pics then select email and it auto resizes them. then I just reselect them in the email browser and copy them back to a file called small pics. these fit on here ok