Bike runs great on starter fluid

[Fj1100 Rebuild project]

I recently got my bike put together for the most part and I got it started... on starter fluid... sounds great and runs on all four, over the weekend when I did my first start I did get it to run on 3 cylinders with no fluid but now it won't even do that... carbs were allegedly cleaned by previous owner and seem to be synched and I appear to be getting fuel from the petcock so I'm kind of stumped

[Flynt]

Are the choke plungers operating properly?  You're going to have a hard time getting it running from cold without a functioning enrichment system, other than on starting fluid.  You don't want to run it on starting fluid btw...

If the choke is working, check to see if fuel is getting into the float bowls.  Next most likely problem is no fuel getting to carbs, and assuming you have a FJ1100 that could easily be the problem if your fuel hose isn't routed correctly.  There's a diagram on the bike that must be followed exactly to avoid issues.

Frank

[Fj1100 Rebuild project]

Are the choke plungers operating properly?  You're going to have a hard time getting it running from cold without a functioning enrichment system, other than on starting fluid.  You don't want to run it on starting fluid btw...

If the choke is working, check to see if fuel is getting into the float bowls.  Next most likely problem is no fuel getting to carbs, and assuming you have a FJ1100 that could easily be the problem if your fuel hose isn't routed correctly.  There's a diagram on the bike that must be followed exactly to avoid issues.

Frank

Yeah I've just been spraying starter fluid into the air box and letting it do its own thing but I don't keep spraying fluid into the carb after it starts I wait for it to die and try again. The choke is seized and I have no clue what's going on there but I live in the middle of the Arizonan desert and none of my other bikes need to be choked to cold start at this time of the year so I figured that's a project for another day. Where is the fuel hose diagram located? Does it give me measurements? I just guesstimated sizes and threw two 3/8 inch hoses on it connected to a brass T fitting and connected that to a inline filter and the hose that was already on the tank. I went out after I posted this and did get the bike running but it only runs on all 4 at around 5k rpm and feels really sluggish on the throttle. Thanks for the info I'll go check the fuel lines and see if the tank is pinching or something

[red]

I recently got my bike put together for the most part and I got it started... on starter fluid... sounds great and runs on all four, over the weekend when I did my first start I did get it to run on 3 cylinders with no fluid but now it won't even do that... carbs were allegedly cleaned by previous owner and seem to be synched and I appear to be getting fuel from the petcock so I'm kind of stumped

Fj,

Sounds like you have a fuel problem (only), so don't repair anything yet.  If the bike has been sitting idle, I would drain (siphon) out all of the old fuel.  If you can, also dump the old fuel now in the float bowls, but that is not too important here.  Add carb/injector cleaner to label specs in new fuel, and put that into the tank.  Crank the engine a bit, once or twice a day, until it starts.  Use starter fluid briefly, and only if necessary; it can wash the oil off of the cylinder walls.  Patience counts, here. Fuel injector cleaner is magic stuff, but not instant magic.  Best of luck.

[red]

Fj,

Try it without the inline fuel filter.  Gravity feed is not sufficient for a fuel filter, except maybe the metal-mesh filters (not the porous brass types).

[Fj1100 Rebuild project]

Fj,

Try it without the inline fuel filter.  Gravity feed is not sufficient for a fuel filter, except maybe the metal-mesh filters (not the porous brass types).

I pulled the filter off and redid the fuel lines low and behold I got it to run, however I'm having misfiring issues, put the heat gun to the headers and noticed while my right side headers were running 470-500 degrees my left headers were only at 160-200 degrees... any thoughts? Seems to me like I have a 2 cylinder misfire

[RPM - Robert]

Most of the time the carbs are still dirty. It doesn't take more than 2-3 weeks of sitting around with the high ethanol content for the fuel to cause problems in the pilot circuit.

[Flynt]

Get some fresh gas and some Techron fuel cleaner in it...  then ride it for a while and see if it improves.  If the carbs were really clean and balanced, this will clean them up pretty well.  Once they're really dirty this won't work, so you'll know if they are really clean enough or not.  I'd also verify balance on the carbs...  what you have sounds like carbs out of synch.

Frank

PS - the fuel line routing is shown on a sticker on the airbox I think...  Father Pat will jump in shortly to bring you to salvation in that one.  Must be right line, right routing, right needles/seats, and right float heights or the whole thing's not going to work right.

[Fj1100 Rebuild project]

Get some fresh gas and some Techron fuel cleaner in it...  then ride it for a while and see if it improves.  If the carbs were really clean and balanced, this will clean them up pretty well.  Once they're really dirty this won't work, so you'll know if they are really clean enough or not.  I'd also verify balance on the carbs...  what you have sounds like carbs out of synch.

Frank

PS - the fuel line routing is shown on a sticker on the airbox I think...  Father Pat will jump in shortly to bring you to salvation in that one.  Must be right line, right routing, right needles/seats, and right float heights or the whole thing's not going to work right.

Alright thanks for the info, ran it a bit more and I may have gotten cylinder one back heat gun reads 540 now, seems like I get all 4 back at about 3k rpm but cylinder 2 is still the lowest at 360 on the heat gun. I'll throw some cleaner in the tank put some fluid in the clutch master cylinder and try to ride it a bit tonight

[Pat Conlon]

Most of the time the carbs are still dirty. It doesn't take more than 2-3 weeks of sitting around with the high ethanol content for the fuel to cause problems in the pilot circuit.

This ^^^

If your choke plungers are stuck, that's a clue...your choke and idle circuits are clogged.

[RPM - Robert]

Get some fresh gas and some Techron fuel cleaner in it...  then ride it for a while and see if it improves.  If the carbs were really clean and balanced, this will clean them up pretty well.  Once they're really dirty this won't work, so you'll know if they are really clean enough or not.  I'd also verify balance on the carbs...  what you have sounds like carbs out of synch.

Frank

PS - the fuel line routing is shown on a sticker on the airbox I think...  Father Pat will jump in shortly to bring you to salvation in that one.  Must be right line, right routing, right needles/seats, and right float heights or the whole thing's not going to work right.

Alright thanks for the info, ran it a bit more and I may have gotten cylinder one back heat gun reads 540 now, seems like I get all 4 back at about 3k rpm but cylinder 2 is still the lowest at 360 on the heat gun. I'll throw some cleaner in the tank put some fluid in the clutch master cylinder and try to ride it a bit tonight

Running like junk at idle/missing cylinders and cleaning up at higher rpm definitely points to a dirty pilot circuit.

[RPM - Robert]

Are the choke plungers operating properly?  You're going to have a hard time getting it running from cold without a functioning enrichment system, other than on starting fluid.  You don't want to run it on starting fluid btw...

If the choke is working, check to see if fuel is getting into the float bowls.  Next most likely problem is no fuel getting to carbs, and assuming you have a FJ1100 that could easily be the problem if your fuel hose isn't routed correctly.  There's a diagram on the bike that must be followed exactly to avoid issues.

Frank

Yeah I've just been spraying starter fluid into the air box and letting it do its own thing but I don't keep spraying fluid into the carb after it starts I wait for it to die and try again. The choke is seized and I have no clue what's going on there but I live in the middle of the Arizonan desert and none of my other bikes need to be choked to cold start at this time of the year so I figured that's a project for another day. Where is the fuel hose diagram located? Does it give me measurements? I just guesstimated sizes and threw two 3/8 inch hoses on it connected to a brass T fitting and connected that to a inline filter and the hose that was already on the tank. I went out after I posted this and did get the bike running but it only runs on all 4 at around 5k rpm and feels really sluggish on the throttle. Thanks for the info I'll go check the fuel lines and see if the tank is pinching or something

3/8 is as good as you are going to get stateside. They are 10mm but not available to buy direct from Yamaha so 3/8 is a close as you are going to get.

[Fj1100 Rebuild project]

Are the choke plungers operating properly?  You're going to have a hard time getting it running from cold without a functioning enrichment system, other than on starting fluid.  You don't want to run it on starting fluid btw...

If the choke is working, check to see if fuel is getting into the float bowls.  Next most likely problem is no fuel getting to carbs, and assuming you have a FJ1100 that could easily be the problem if your fuel hose isn't routed correctly.  There's a diagram on the bike that must be followed exactly to avoid issues.

Frank

Yeah I've just been spraying starter fluid into the air box and letting it do its own thing but I don't keep spraying fluid into the carb after it starts I wait for it to die and try again. The choke is seized and I have no clue what's going on there but I live in the middle of the Arizonan desert and none of my other bikes need to be choked to cold start at this time of the year so I figured that's a project for another day. Where is the fuel hose diagram located? Does it give me measurements? I just guesstimated sizes and threw two 3/8 inch hoses on it connected to a brass T fitting and connected that to a inline filter and the hose that was already on the tank. I went out after I posted this and did get the bike running but it only runs on all 4 at around 5k rpm and feels really sluggish on the throttle. Thanks for the info I'll go check the fuel lines and see if the tank is pinching or something

3/8 is as good as you are going to get stateside. They are 10mm but not available to buy direct from Yamaha so 3/8 is a close as you are going to get.

Ok good to know, bike finally seems to be running on all 4 at idle now and I got it to start with no starter fluid so issue is definitely improving... now I need to get the idle set properly and I'll be good to go

[ajacstern]

Would definitely recommend a thorough carb clean, either meticulously by hand or with assistance of an ultrasonic machine and then a good sync. Almost always provides a massive improvement in running and reliability. Fiddling with the jetting after that will provide some gains as well depending on what jetting you have now. These bikes have some of the most reliable and tolerant carbs of any bike I have worked on, but there are definitely improvements to be had by getting the fueling dialed in.