Today's lower octanes are much cleaner, etc, than yrs past. Its fine to run the 89 in your F4. Personally, I try to avoid any type of fuel that has detergents or additives that aren't necessary. Too, I try to stay w/ big name stations. Often times, the no-name places will have many additives that stretch the fuel.

Good luck w/ your hesitation problem. Once diagnosed, it shouldn't be hard fix. My rectifier went out last yr & was a real pain til I finally figured out it was the cause.

 

Umm.. Thread from 2007

 

Hey Mike, any time you're having acceleration issues, the main cause is of course clogged carb jets... but, most people tend to overlook the TPS (throttle postition sensor). It plays a major role in the bikes acceleration and once it gets heated up by the engine, it may fault. It's a pain in the *ss to replace unless you have a T10 anti-tamper torx bit, cut it down so you can get a wrench on it. Otherwise you have to pull the carb assembly to replace it. Ohm yours out to make sure before proceeding tho. Measure the ohms from the ICM connection at the the yellow/blue and blue/green wires, value should be 4 to 6 Kohms and should vary steadily with throttle movement. IF you see a glitch or infinity reading while twisting the throttle, chances are the TPS is faulty and causing hesitation.

 

well 76 has 100 at the pump and i wouldnt use boosters,theyre a joke,if it says up to 7 points it means .7 so if you use 91 it jumps to 91.7 if you lucky,boosters also breaks up junk in you fuel system then puts it through your carbs which is no good

 

hey mike i had a similar problem with my 2000 f4 and it was the spark plugs,and also i have had a problem with my coil getting too hot and acting funny,i first cleaned my plugs which helped for a couple days then just bought new ones,also check spark after it starts to mess up

 

I am having the exact same issues. I have put in new spark plugs, new K&N Air Filter, New Water Sensor (can remember the official name of it, it's on the radiator), and I have burped the system until I saw no more air bubbles. The only thing I have not done is synced the carbs and went with a higher octane gas. Has anyone solved this issue? I'm about to drain all the coolant and put fresh new coolant in. I don't think it's the charging system, because the bike fires right back up. Is there a recall on this at all? Anyone get a clear definite fix for this yet? This is driving me nuts, it makes it seem like you are a beginner, not being able to pull off in first gear or riding the clutch as you pull off!

 

I'm having the issue too and have just been dealing with it. My bike is in the shop for an unrelated issue. I'm going to try to adjust my idle screw to have the bike idle a little higher. What is your bike idling at normally and when it feels like it's going to die?

Also I have done a coolant flush and it didn't affect it at all...it could be the fan but I'm going to try adjusting the idle first before going to that.

 

I had this issue when I first bought my bike. I fought with it for months. One of my buddy's suggested a new battery even though my battery was testing out fine.

A new battery completely fixed the problem for me. My thoughts are that the battery is fine when not under continuous large loads by itself (i.e. starting, running over 3k rpms, ect.) However, when you stop at a light and the bike is really hot, the available amps from the battery drop just below what is needed to operate and it starts to choke. Then, when it stalls, you are able to start again because the battery had a second to level out and the bike runs again.

Not sure if this is precisely correct (Being a mechanical engineer I know just enough about electricity to be dangerous ), but it worked for me.

 

My battery is still pretty new put I did just get my bike back and adjusted the idle to be at around 1500-1600 rpm and it didn't die on me earlier or even sound like it wanted to even when the bike got hot and it would normally cut out.

 

I am having the same problem. I will be switching to a higher octane gas once I run this tank out. On the spark plug situation, has anyone had a better experience with a certain brand or style ie. platinum 4 vs platinum 2.....?