2005 RX-1 Performance Question

[Bob Miller]

Thanks Len

 

[yamahamaniac]

Something like this has happened to mine since I brought it to my dealer this year to get serviced. Since they cleaned the carbs she has great trouble idling when she's warming up and when she first gets warmed up and I hit the throttle she dies then takes off. She dies enough to throw you forward if you are only going like 10km/h. Before I brought her in the this never happened, perfect idle while warming and never any hesitation. Brought her back in and they pick apart the carbs again and say they can't find anything wrong. I don't know if I trust their opinion of nothing wrong.

 

[Len Todd]

A "bad idle" is typically traced back to the Pilot Jets being dirty or plugged. The exact symptom for a dirty or plugged Pilot Jet is when you blip the throttle, the sled does not drop back down to your pre-set idle RPM. It does this because it is running a bit lean.

Also, I had to clean my Carbs 3 times this year. The jets were cleaned and they plugged right back up. After the second cleaning, I also shocked the fuel system with cleaner. After cleaning the carbs the second time, she ran fine, for a few miles. But, all of a sudden I lost a cylinder. On the third cleaning I discovered that a Main Jet and a couple Pilot Jets were plugged and there was goop/flakes in the carb bowls. These deposits were too large to have passed through the needle valve. The excessive cleaner had loosened the deposits from the fuel system and the deposits gelled in the carb.

To get a Pilot Jet clean, I soak them in carb cleaner for a few minutes. Then, I "rod out" the Pilot Jet with a bristle from a wire brush. To make sure it is clean, then I spray carb cleaner through it. If you put the carb cleaner's red tube to the slotted end of the jet and seal the slots with your fingers, a squirt of carb cleaner will shoot about 10' in a nice even spray. If you do not see that nice even spray shoot for 10', then it is not clean, even if you can see light through the Pilot Jet.

Inspect the coils for shorting into the valve cover. To inspect the coils: Remove coils, take the centering grommet off the coil, install coil carefully centering them in the valve cover’s hole, start sled, darken room, look down into coil hole for arcing. Any arcing and the coil and/or the spark plug needs to be cleaned or replaced. You can take the rubber tips off the coils and clean down inside the rubber tip also. Clean the coil and the rubber tip with carb cleaner to remove any carbon tracking. Then apply dielectric grease and reinstall the rubber tip. Put dielectric grease on the plug too. If you still see arcing, you are in for a new coil. But, make sure you have the coil centered when you are looking for arcing.

A rough idle symptom may indicate the need for syncing the carbs. When you have the jets clean, the coils NOT arcing and the carbs synced, these babies purr like a kitten and run like a raped rabbit.

 

[yamahamaniac]

Thanks for the reply Len, but my problem is only within the first 10 - 20 mins of her getting started when she's cold. Then after tht she seems to work fine. What you just described to me is for when the sled doesn't idle well at all isn't it?

 

[Len Todd]

I never move the sled until the "Warming Indicator" stops blinking. After the indicator stops blinking, I start rolling the sled slowly. Mine will idle normally after the light goes off with the choke off. Mine will not stall after about 15 seconds after starting, with the choke off.

I am thinking that your carbs are your problem. If the sled is stalling, it is either the fuel or the coils. So, ... you either have to clean the carbs or clean the coils. If you do not do one or the other or both, you will have to live with the problem.

 

[yamahamaniac]

I don't move the sled until the light goes off either. Go slow for a bit then drive it like I stole it. I'd say it must be the coils. Had her to the shop twice including the first time when they serviced her and the second time they said the couldn't see any problems with the carbs. If the coils were dirty would that kill the sled? Like motor blown suicide?

 

[Len Todd]

I had to clean the carbs three times this year. They were clean and plugged back up becasue of contamination in the fuel, twice!

 

[yamahamaniac]

But the second time he took the carbs off he said there was no dirt in them at all. There was a very miniscule amount in them the first time. So it must be something other than the carbs??

 

[bigal1951]

The pilot screws are not in the float chamber. They are located in the bottom of the Carb discharge throat. Just before the area where the intake boot clamps on the carb.

Hey, Len. Can you adjust the pilot screws without taking the carbs off?

 

[rxrobmeyers]

Pilot screws should be removed to clean the carbs properly, careful of the little bits, and pilot needle prone to breaking, careful when closing before you back it off. Forget the number of turns for that. Pilot screws access is from below with carbs mounted and for me no clearance to adjust, so they come off. Haven't seen this mentioned yet, and maybe nothing, but I understand these carbs are heated. So thinking if your problem only occurs for first 10 - 20 minutes, maybe choke cycle is properly finished, engine coolant warming, but maybe carb heater not fully on, causing hesitation at the carb. Total guess, but that 10-20 minutes is likely the carb heat cycle. I know my grips heater, is same takes about 10-20 mins to come on.

 

[Indy]

Hey, Len. Can you adjust the pilot screws without taking the carbs off?

This thread is over 7 years old!

 

[rxrobmeyers]

Thats hilarious, totally fell for the last poster comment. Lesson learned ...its not so fun when you bury a corpse and it floats up 7 years later...

 

[bigal1951]

OK; maybe I should explain my exact problem. I have tried everything and still have a growl rather than a sharp bark when I accelerate. I have completely rebuilt the carbs with the exception of the pilot screws because one carb was pissing fuel. Before the rebuild and the one carb pissing fuel the sled ran great. The carb pissing fuel had a stuck open needle. Rebuild went fine and when I put the carbs back on, the sled started up and ran fine. New plugs were installed. When I rapped the throttle it struggled to build rpm. There was no backfiring or popping. Just an annoying studder. Took it on the trail and you could definitely feel it was not running crisp to rpm; but, it would get up to rpm. I synced the carbs and found that they were out; but, the problem continues. Could it be the spark plug coils? I am lost now and might have to take it to a dealer; but, am still hoping I can sort this out myself. Any help would be greatly appreciated. Thanks.

 

[maim]

all the top cover o-rings in place correctly? the other o-rings all good?

 

[bigal1951]

Changed all O rings on the jets. Maybe coils????