2003 stumble when launching

[ANZAC]

Also, i can let the clutch out slowly and have the bike pull away but any throttle below 2000 will have the bike starving for fuel. The revs then need to be brought above 2000 and slip the clutch to keep the bike stable.

 

[Fred W]

I will be using her as a commuter so I need the best low speed throttle response to safely ride in everyday traffic.

In that case, just suck it up and buy the PCIII. I did.

When you get one I have a very good map for 1st gens that you can try. It is far smoother than the ones available from DynoTune. It is the Ryan Schnitz Custom Map listed on my web repository (Click the little nerdy guy in my sig line to get to it)

 

[Mihalis fjr]

Also, i can let the clutch out slowly and have the bike pull away but any throttle below 2000 will have the bike starving for fuel. The revs then need to be brought above 2000 and slip the clutch to keep the bike stable.

The solution:

 

[bunky]

to anyone following alone with this problem this is bunky I had this problem until someone

mentioned bad gas. I bought some Rislone 4700 put it in one gallon of gas ran the bike at

idle for a few minutes shut it down for ten then went for a slow 2K in 4th .and 5th ride for

a half hour and presto, 80% better than before. It's now raining pretty good for the first time

in many months so I will stay out of the wet grease for now, but it sure seems a LOT better.

BTW I have a power commander and used it prior to the additive to change mixture with no benefit.

 

[ANZAC]

It seems the Power Commanders will work but you have to get the right maps or massage the settings until you get it running right. Other factors are air filters, bad gas, vacuum leaks, TPS, plugs etc...

My next step is to take out the K&N air filter, put in the stock like filter and disconnect the O2 sensor. Not sure if I want to goof around with the jumper mods but then again it's free

 

[Mihalis fjr]

It seems the Power Commanders will work but you have to get the right maps or massage the settings until you get it running right. Other factors are air filters, bad gas, vacuum leaks, TPS, plugs etc... My next step is to take out the K&N air filter, put in the stock like filter and disconnect the O2 sensor. Not sure if I want to goof around with the jumper mods but then again it's free

Whatever map you will install in the PCIII,immediately you will notice a big difference!!Between the stock ECU map & PCIII map...

 

[Denver_FJR]

... Other factors are air filters, bad gas, vacuum leaks, TPS, plugs etc...

Yep, certainly any of those could cause problems and since I hate to doing more work than necessary, wanted to throw this concept out for the group... Shouldn't the TB sync bear out a vacuum leak? That is, if all cylinders balance without gross adjustment and are within spec (9.8 inHg) (250 mmHg), shouldn't this indicate no leaks?

 

[RaYzerman19]

Best check the hoses and vacuum caps independently. E.g., when you hook up for the TB you are removing the caps, any of which could be cracked and might leak when you put them back on....... same would apply for a cruise hose, if you have cruise.

 

[bunky]

I have replied to this problem before and thought bad gas

ignition plugs etc. I tried a lot and the problem never went away

I eventually just started giving more gas at launch to avoid the stumbling.

Today I got off a freeway and came to a stop and my clutch all but failed.

I nurse her home and took of the master cylinder cap and found almost

nothing but a 1/2 teaspoon of coffee colored liquid. Holey Moly!

I DID NOTHING but buy a large can of DOT4 and flush the crap out of the

system. When done I went for a ride and the clutch was as new.

But after a minute of joy I was further delighted to find that the

stumble is completely utterly GONE! Not a hint. I have been scratching

my head for the last 3 hours. I reviewed everything I did, look to see if I

moved any wires, contacts and nothing, I just purged the clutch hydraulics.

One thing I would note is that during the problem, many times I would bring the

bike to stalling in second and third gear and slowly open the throttle and never a

stumble. At some point I began to suspect first gear and shifting was the problem

not a general engine problem. Anyway, that is my experience, I have no clue why

and no idea if it will help you guys, good luck. It much nicer to be able to pull smoothly

away from a stop

Bunky

 

[ANZAC]

My bike ran better after I flushed the clutch too. I have just replaced the spark plugs with CR8EIX iridium plugs. This made quite a difference as well. Remember these bike are 10 years old and now fed ethanol type fuel which is just slightly better than tap water.

The other thing is I got an Accelerator Module and just put a few miles on her. What I can say is the throttle is much smoother and hesitation is 90% gone. Time will tell as I stack the miles on so stay tuned.

 

[puppychow]

Shameless Plug - If you are still looking for a PCIII - I have one for sale in the For Sale section. It has the Wally Smoothness map pre-loaded, but you can load whatever map you want, if you have a laptop and a USB to mini-USB cable. Hope it solves your issue.

 

[ANZAC]

I saw your add for the PCIII just after I got my AM. Why are you selling? That's a really good price!

 

[puppychow]

I saw your add for the PCIII just after I got my AM. Why are you selling? That's a really good price!

Why am I selling? Because I haven't been using it. My FJR runs rich as it is - don't need a PCIII to add fuel to smooth it out.

It IS a really good price, I bought it on the forum used for more than that, hopefully whoever buys it will send some goodwill over in addition to the price of the PCIII.

 

[Bustanut joker]

Might be too much alcohol in the fuel.. I know I stumble when I drink too much.

 

[ANZAC]

Might be too much alcohol in the fuel.. I know I stumble when I drink too much.

Well, the Accelerator Module seems to have given better throttle response and less stumbling in the lower rev range which is what I need for Portlandia traffic slogging. Not sure how it would work when drinking too much alcohol

 

[ANZAC]

Hey guys

Thought I would update this thread. I tried the Accelerator Module and it did help to a minor amount but still the bike is hard to modulate throttle below 2000. I also replaced the fuel pressure regulator as well and ran lots of fuel treatment through the bike. My mileage goes between 35 to 39 mpg with lots of commuting - not clear sailing down the interstate with the sun and wind at your back

Just placed an order for the Power Commander 3 which will arrive on the 16th. Reading all the older threads and trying everything under the sun to make sure I have correctly working engine, has me putting all hopes on the PC3.

I will be looking up the best map to use such as Wally's smoothness or the one Fred has to give me the smoothness and throttle control I need. Wish me luck as I am getting tired of feeding so much throttle and feathering the clutch to keep her from hesitating and stumbling.

 

[Mihalis fjr]

Hey guys
Thought I would update this thread. I tried the Accelerator Module and it did help to a minor amount but still the bike is hard to modulate throttle below 2000. I also replaced the fuel pressure regulator as well and ran lots of fuel treatment through the bike. My mileage goes between 35 to 39 mpg with lots of commuting - not clear sailing down the interstate with the sun and wind at your back

Just placed an order for the Power Commander 3 which will arrive on the 16th. Reading all the older threads and trying everything under the sun to make sure I have correctly working engine, has me putting all hopes on the PC3.

I will be looking up the best map to use such as Wally's smoothness or the one Fred has to give me the smoothness and throttle control I need. Wish me luck as I am getting tired of feeding so much throttle and feathering the clutch to keep her from hesitating and stumbling.

The PC3 solved the same problem in my bike 90%+!I run the European map now and works very good.I believe that your problem will solved with the PC3!

 

[ANZAC]

Thanks Mihalis - you, Fred and lots of other riders have me convinced that this will work. At least I will have the ability to play with the FI mapping like adjusting the carburetor mixture screws for proper engine operation.

 

[ANZAC]

Also, i can let the clutch out slowly and have the bike pull away but any throttle below 2000 will have the bike starving for fuel. The revs then need to be brought above 2000 and slip the clutch to keep the bike stable.

The solution:

[img=[URL="https://i1270.photobucket.com/albums/jj620/mihalisfjr1300/0000_dynojet_power_commander_iii_usb_plastic_zps93022867.jpg%5D"]https://i1270.photobucket.com/albums/jj620/mihalisfjr1300/0000_dynojet_power_commander_iii_usb_plastic_zps93022867.jpg][/URL]

Yes, Mihalis was right - the Power Commander 3 was the answer. I finally got mine in, loade the Ryan map and installed yesterday. When I first ran the bike it seemed nothing much changed then I realized that I had forgotten to disconnect the O2 sensor. The bike ran much better but still something was not right. Looking through the archives and the FJR Tech stuff regarding Power Commanders I noticed that the throttle position needed to be defined correctly for idle and WOT. I followed Wally's directions and noted that the displayed idle number for the zero setting was like 4800 and the actual idle value was about 2480. So I reset the values, got the zero setting to match the idle the wacked the throttle to set the 100% number and saved the settings.

The bike is now like a different animal. Very smooth linear power down low and up at highway speeds. The engine runs cooler as well as I did not see my normal three bars. 80mph is the new 60mph - the bike is that much different.

Thanks again for everyone's help

 

[Mihalis fjr]

Also, i can let the clutch out slowly and have the bike pull away but any throttle below 2000 will have the bike starving for fuel. The revs then need to be brought above 2000 and slip the clutch to keep the bike stable.

The solution:
[img=[URL="https://i1270.photobucket.com/albums/jj620/mihalisfjr1300/0000_dynojet_power_commander_iii_usb_plastic_zps93022867.jpg%5D"]https://i1270.photobucket.com/albums/jj620/mihalisfjr1300/0000_dynojet_power_commander_iii_usb_plastic_zps93022867.jpg][/URL]

Yes, Mihalis was right - the Power Commander 3 was the answer. I finally got mine in, loade the Ryan map and installed yesterday. When I first ran the bike it seemed nothing much changed then I realized that I had forgotten to disconnect the O2 sensor. The bike ran much better but still something was not right. Looking through the archives and the FJR Tech stuff regarding Power Commanders I noticed that the throttle position needed to be defined correctly for idle and WOT. I followed Wally's directions and noted that the displayed idle number for the zero setting was like 4800 and the actual idle value was about 2480. So I reset the values, got the zero setting to match the idle the wacked the throttle to set the 100% number and saved the settings.
The bike is now like a different animal. Very smooth linear power down low and up at highway speeds. The engine runs cooler as well as I did not see my normal three bars. 80mph is the new 60mph - the bike is that much different.

Thanks again for everyone's help

Really glad that your problem has resolved!!