My 2003 is unresponsive sometimes - No getup and go

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

tophog

Well-known member
Joined
Mar 29, 2007
Messages
160
Reaction score
0
Location
Salem, OR
I've searched but didn't really find anything, then again I could be searching based on the wrong keywords ...

I have a 2003 FJR with 12K miles. I just bought it from the OP about 2 months ago. Since it was at 12K I went ahead and did all the typical maint. items ...installed new plugs, changed oil/filter, new air filter, rear gear oil, new tires, etc. I also have a morgan carb tune from my previous 2007 FJR and other bikes that I did TB syncs on so I also performed a TB sync. It was out quite a bit as I don't think it had ever been done since new.

The bike seems to run/idle fine most of the time however on occasion when I really get on the throttle it feels like it doesn't have immediate throttle response ...I wouldn't say it's bogging down but at the same time it really doesn't pickup speed like it should. It doesn't seem to miss or anything ...I guess it could be described as lack of power. My 07 did the same thing ...but that was the due to the altitude sickness TSB. It should take off like a scalded cat when I got WOT no?

What are some things I can check? Not knowing if the bike sat for a long time with old fuel I filled it up with premium the first tank and ran some injector cleaner thru it ...but that doesn't seem to have helped.

Thoughts?

 
Last edited by a moderator:
Just a thought, have you verified that you are indeed getting WOT when you twist the grip?

Throttle cable adjustment might be off. Sounds like you've covered the basics.

 
I checked the TPS sensor range and it looks correct ...linear and full range. As for the throttle I don't have to go to WOT...I can be cruising at 50 mph and got 3/4 throttle and can tell it's not taking off like it should.

Just a thought, have you verified that you are indeed getting WOT when you twist the grip?

Throttle cable adjustment might be off. Sounds like you've covered the basics.
 
Do you know if the orifinal owner ever had the valves adjusted or the CCT changed? It is highly unlikely at such low miles but one of the cams could be off by one tooth.

The other thing I thought of is gunk or rust in the fuel tank preventing full flow.

 
I don't think the bike has ever been to a dealer. The OP told me he bought it and rode it and had no problems with it. Who knows ... At least there is no tick ... yet :) The tank looked clean from what I could tell by draining some fuel out and inspecting inside of tank with a flash light.

Do you know if the orifinal owner ever had the valves adjusted or the CCT changed? It is highly unlikely at such low miles but one of the cams could be off by one tooth.

The other thing I thought of is gunk or rust in the fuel tank preventing full flow.
 
Last edited by a moderator:
To be honest I haven't ridden it enough to really hone in on the RPM range, etc. I never noticed it before I did the maint. stuff on it so I'm not sure if it was doing it before I bought it or not. I would like to think so. I basically bought it, rode it home where it sat for a month while it rained ...and that's when I did the maint. on it. I don't think I mucked anything up with plugs, TB sync, etc. as I'm fairly meticulous when it comes to wrenching, etc. That said I'm not ruling anything out.

I need to get out on it and try and isolate the problem if possible as to rpm range, etc. The first time I went out I road it for about an hour casually ...then got on some back roads and got more spirited down a straight stretch and that's when I decided to open it up ...and that's when I noticed it. I was thinking to myself wTF? ... I was still on the original gas and chalked it up to bad gas. Several days later (after it quit raining again) I filled it with premium and put a bottle of Chevron cleaner in the tank. Road it to work freeway one day (100 miles r/t) and forgot about the problem and forgot to test. I went out last weekend and the problem persist.

Is it happening at a certain RPM, like between 4-5k?
 
I should have stated initially that I did find that thread in searching and already took it apart and inspected. I did find a tad bit white/green corrosion on a few terminals but cleaned and siliconed already. Perhaps I need to pull it apart again and do a better job as it does sound exactly what my symptoms are.

Top,

Check out your Main Harness Connector... the GenI version of the Spider situation:

https://www.fjrforum.com/forum//index.php?s=&showtopic=22734&view=findpost&p=268059

Here is another response from RAD on his bike:

https://www.fjrforum.com/forum//index.php?s=&showtopic=105232&view=findpost&p=450507
 
Last edited by a moderator:
To be honest I haven't ridden it enough to really hone in on the RPM range, etc. I never noticed it before I did the maint. stuff on it so I'm not sure if it was doing it before I bought it or not. I would like to think so. I basically bought it, rode it home where it sat for a month while it rained ...and that's when I did the maint. on it. I don't think I mucked anything up with plugs, TB sync, etc. as I'm fairly meticulous when it comes to wrenching, etc. That said I'm not ruling anything out.

I need to get out on it and try and isolate the problem if possible as to rpm range, etc. The first time I went out I road it for about an hour casually ...then got on some back roads and got more spirited down a straight stretch and that's when I decided to open it up ...and that's when I noticed it. I was thinking to myself wTF? ... I was still on the original gas and chalked it up to bad gas. Several days later (after it quit raining again) I filled it with premium and put a bottle of Chevron cleaner in the tank. Road it to work freeway one day (100 miles r/t) and forgot about the problem and forgot to test. I went out last weekend and the problem persist.

Is it happening at a certain RPM, like between 4-5k?
Only reason I ask is because it sounds similar to mine. Between 3-4k it wants to rip your arms off and at 4k the power seems to level out. It's still there but much less substantial, kind of a "stuck in the mud" feeling in the power. Does that sound like what you're describing?

 
You've got a 9 Y.O. motorcycle that's been ridden a little over 1K miles/Yr.

If you live in a damp climate, you could have seriously compromised brake hyfraulics. After riding, feel for heat in your brake rotors -- they could be self-applying? And reducing any surplus H.P.

(I had a buddy who bought a garage-queen, non-FJR, and the (contaminated) front brakes came-on so hard they stopped the bike on a mountain road, down-hill, in traffic, all on their own...! :eek: )

Spark/compression/fuel -- do the spark-plugs look clean? Compression tests are easy to do...

In lieu of a (preferred) shop dyno-run, an open road along with WFO throttle should see a flat 150 MPH relatively easily -- the 'poor man's dyno'. If you bike doesn't walk right up to top speed, it's different from 'normal' -- if it does, it's probably OK.

 
Last edited by a moderator:
Top