Starting problems with f3!!!!!
 

Ok so i bought this 97 f3, and it was so cold out the battery wouldn't hold a charge to turn over. So i bring the bile back to my house, swap batteries with my 95 f3 and all it did was turn over until the battery died. The next day i took the battery back out and put it on a battery tender, and started cleaning the carbs. ( I read some forums that a/f is a very common problem. Also the bike has a k&n and sudco exhaust). I checked the spark by grounding all the plugs and wires to the frame. all tested to be fine. i reassembled everything. put fresh gas in, AND.... same results. So back to the a/f. I figured the bike was to lean and swaped, i think the main jets, which were kehin brand (i was told these were stage 3 jets, they were noticablly larger . There was also these other jets and all of them said 40s. My other set of carbs had 40s-38s-40s-38s pattern. reassembled yet again. same results, also gas was pluming out of the exhaust. I took the spark plugs out and they were wet but still arced to the frame. I've tried swapping out the r/r and fuel pump, fuel pump relay, cleaned the fuel filter, and connect the bike to my truck. I understand that you need fuel, spark, air, and compression. i have all of these. timing is also spot on. The only promising thing that happened was yesterday the bike made a full revolution on ether. So any help would be awesome. I have a spare f3 to trouble shoot parts with. Thanks in advanced for any help.

My f2 did exactly this, unfortunately I can't be of much help. After 2 days of tuning and cranking off a car battery, it started and runs fine now. I did absolutely nothing but crank-crank-crank, so I still have no idea what the problem is.

Hope someone can give a better solution.

Well you said you have:

Spark-X
Fuel-X
Air? Check the airbox for blockages?
Compression? Have you checked all the cylinders just for ****s and giggles?
Ignition Timing? Sure you have spark at the right time? Strong enough spark?
Valve timing? Sure you have valves open and closed at the same time? This would go hand in hand with having compression.

I would assume with the K&N and pipe it's been jetted to provide more fuel and also tuned to provide more fuel and air. If the plugs are wet and it's got spark (granted it's at the right time) you would be the opposite of lean... rich. Put the carbs back to factory settings and start from their. Did the carbs on those have adjustable floats?

Compression is good? What is it? My hunch is it's low.
Something that can happen is if fuel is leaking into the cylinder it can "wash" away oil on the cylinder walls. This WILL result in a loss of compression significant enough where it won't start. Check comp. and post results.....
Also, look at the quality of the spark on the plug when you have it touching the frame. You want a nice blue color and the ark shouldn't jump to different spots on the ground electrode.

Check the compression. Spec is 185-191psi. Spark plugs could be old & fouled. I have seen plugs that spark outside the combustion chamber & wont spark under compression. Stock slow speed jet is #40. 1&4 main is 135, 2&3 is 138. Set the fuel mixture screw at about 2 1/2. The floats are not adjustable on these models. Fuel washing away the oil in the cylinder should not have noticable difference if the rings are good. If they are bad then the compression reading will be low anyway. A leakdown test will confirm this. Does the other F3 you have run? If so try taking the cabrs off of it & put them on the questionable one & try throwing a new set of spark plugs in there. Post back with results.

Well one thing is unless the carbs were tuned, your main jets are off. Ignoring different manufacturer's numbering system, carbs 2 & 3 should have larger main jets than carb 1 & 4.

With all the yanking and pulling are you absolutely positively sure the spark plug leads are in the correct order?

fyi...stage three jets are pretty large and for a completly diferent set up than a mildly modded bike. did the bike run when u bought it? did u hear it run?

Well unfortunetly i cant trouble shoot the bike today, but i will try a couple of your guys ideas. I did not ever see it run, although i did check absolutly everything. I had a really bad experience with another f3. My other f3 had a warped head and it built pressure in the cooling system, and when it got hot enough it blew a radiator hose all over me doing 65 mph. so ya, sucked ballz. Any how.... I know for sure that the crankshaft and cams are in time, spark plugs are in order (has what order they are in on the plugs, coil packs are hooked up to the coorrect wires and plug wires, theres oil in the engine, there is no blockage of any sort, well lets just say i spent hours reading forums and applying those ideas to the bike. When i bought the bike, the guy lived in cali. So i assumed the bike sat for some time. He said he rode it a week ago before i bought it. But the night before i came to pick it up he tried to start it for me over the phone and he killed the battery from cranking and cranking. He thought it was the starter. I have a feeling that he flooded cylinders which fouled out the plugs. But the plugs still spark???? The reason why i assumed that it was lean, was because the spark plugs had signs of being burnt. I am going to pick up some new plugs in the morning. The only thing i can think of that could be wrong is valve clearences (25,000 miles on the bike, i have heard of bikes getting up in the 50,000 mile range or better and still run like new), to rich from carb since gas is present in the exhaust, the spark box is shorted out and it could possibly throw my ignition timing off, or the current spark plugs suck... Sorry for the book. I hope this help guys.

well strange enough my bike started. All i did was crank crank and crank, with a wee bit of ether. then i started get these blips of it trying to start. so i turn up the idle and brown chicken brown cow it started. but reved to like 9 k and it was totally unexpecting it. so warmed it up, road it around for a couple hours. parked the bike and checked the plugs and they looked perfect. im pretty confident that in the beginning it was super lean and needed some cranking over. But thanks for all of you guys for your input.



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