Ok I'm starting to get pissed!! 2005 Fjr 1300 1800 miles. When I blip the throttle or accelerate from idle my bike stumbles and acts like it's missing. I have performed a Throttle body sync. Installed a Power Commander and taken all of the slack out of the throttle cable. Checked for pinched lines dirty connections. Still having the problem. When the bike is idling I notice a minor rattling that appears to be coming from the Catalytic Converter. An excessive amount of heat is also coming off the cats. Could this have anything to do with the stumble? I'm thinking the cat maybe defective or something. I have no idea on what else I should do. Bike not under warranty so I hate to take it to the dealership. I forgot to mention I have also checked the TPS sensor which appears to be working correctly. Anyone have any other ideas on what I should check?
catalytic converter Question (Idle Stumble Problem)
- Thread starter reefkpr
- Start date
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r1byker
Well-known member
Okay, there's going to be lot of people with better technical answers than this, but, it's a 3-year old bike with only 1800 miles. I'm presuming it's sat a lot. It's possible there's a stale gas/gummed up injectors issue. Try a fresh tank of gas, throw in a high quality fuel injector cleaner at double the recommended amount and go for a long and fast ride.....and hope that's all it is. I'm not sure how a defective cat would be a problem unless it's completely clogged. You didn't use leaded, did you?
Yeah it sat alot due to me riding my other bikes. I started and ran it frequently though. I have run two new tanks through it and added some cheveron techron injector cleaner not at double the recommended dose. I will try that and see. Anyone else have other ideas please share. Thanks in advance.
C&C
Well-known member
You may in fact have a broken catalytic converter. They can break inside and cause the rattle you describe (and if they partially block your exhaust stream can cause those symtoms.
charismaticmegafauna
Well-known member
What is the idle speed (rpm)? Should be 1100.
Is the problem only when standing still -- or does it also do it while riding?
John F
Active member
Interesting, I have an 08 that stumbles off of Idle but not all of the time. Seems to do this on when the engine gets fairly warm and then sits for 10 to 30 minutes. Upon restart it stumbles off idle but then smooths out. This has been going on the last couple of thousand miles. Doesn't do it when cold only hot and if it has sat for just a little while before restart.
The bike is only a little over a month old with about 5500 miles, it has not sat around.
Almost acts like a vapor lock problem???
The bike is only a little over a month old with about 5500 miles, it has not sat around.
Almost acts like a vapor lock problem???
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ionbeam
2 FUN
reefkpr, your '05 may be in the range of the TPS recall, do you know if it was done? If not, call or go to a Yamaha dealer's service shop with your VIN in hand and they can look it up. Your symptoms are exactly in line with a bad TPS. If your TPS needs to be replaced have it done before going further in the troubleshooting process. Ask the dealer how many FJR TPS changes they have done. Ask them if they just change the TPS or if they have to remove the fuel rail first. If your FJR will be their first, seek another dealer if you can. If they want to remove the fuel rail, seek another dealer if you can.
The TPS is not vindicated with a static diAG test. My TPS was bad only when hot but still passed the diAG test. Finally I stuck volt meter probes in the TPS connector, Velcro'ed my DMM to the handle bars and went for a ride. As soon as my bike got hot I could see the voltage at the TPS drop out. I changed my TPS well before it became a known bad actor, almost two years later Yamaha reimbursed me 100% for my out of pocket purchase.
If I see your post correctly, your '05 only has 1.8k miles? :blink: (yes you have other bikes). The TPS should be changed if it is in the recall range, but dang, the TPS is a wear-out item, it doesn't suffer from sudden death. It is a good thing that you are running some Techron though the system to get after any varnish that may have formed. Has this been a problem across several tanks or did it suddenly start?
Typically, a broken catalyst bed will only effect high rpm operation or aggressive throttle openings, not smooth, low rpm stuff. To test for a broken cat you need to hook a sync tool to any TB spigot, you only need one. With the engine up to operating temp., smoothly turn up the throttle to close to redline. In a good system the vacuum will keep dropping (moving closer to atmosphere) as engine speed comes up and the vacuum will continue to drop all the way to the area of redline. If the cat is broken the vacuum will go down normally then rise (e.g. go from 5mm to 15mm) in the trouble area. I seriously doubt that you have a broken cat. If you are using a Hg based synch tool, do not suddenly release the throttle or all the Hg will get sucked into the engine
uke: and that's a Bad Thing.
The TPS is not vindicated with a static diAG test. My TPS was bad only when hot but still passed the diAG test. Finally I stuck volt meter probes in the TPS connector, Velcro'ed my DMM to the handle bars and went for a ride. As soon as my bike got hot I could see the voltage at the TPS drop out. I changed my TPS well before it became a known bad actor, almost two years later Yamaha reimbursed me 100% for my out of pocket purchase.
If I see your post correctly, your '05 only has 1.8k miles? :blink: (yes you have other bikes). The TPS should be changed if it is in the recall range, but dang, the TPS is a wear-out item, it doesn't suffer from sudden death. It is a good thing that you are running some Techron though the system to get after any varnish that may have formed. Has this been a problem across several tanks or did it suddenly start?
Typically, a broken catalyst bed will only effect high rpm operation or aggressive throttle openings, not smooth, low rpm stuff. To test for a broken cat you need to hook a sync tool to any TB spigot, you only need one. With the engine up to operating temp., smoothly turn up the throttle to close to redline. In a good system the vacuum will keep dropping (moving closer to atmosphere) as engine speed comes up and the vacuum will continue to drop all the way to the area of redline. If the cat is broken the vacuum will go down normally then rise (e.g. go from 5mm to 15mm) in the trouble area. I seriously doubt that you have a broken cat. If you are using a Hg based synch tool, do not suddenly release the throttle or all the Hg will get sucked into the engine
uke: and that's a Bad Thing.
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