new bike new problems

biker122

Active member
hey guys, im having some trouble with my new to me 91 F2.

Its my first bike, and this is our first season together. When i started it up after the winter, it was leaking gas all over the place. I waited a couple days and the problem fixed itself (im thinking the float valves got un-stuck or the o-rings started working again lol)

now..ive noticed that the idle is kinda rough. when i come to a stop, it takes a while for the rpms to get down to 1500 rpms. And once it gets there, it kinda jumps up and down +/- 200 rpms.

Also, when the bike is cold, the throttle response is pretty bad. But once it warms up, it revs like no tomorrow with even the slightest flick of the wrist.
Since the bike is new to me, I can't tell if these problems are new or just there because the bike is so old.

Any help would be appreciated.
 
sounds to me like carb problem.

BTW, when the bike is cold its suppose to be unresponsive especially if its carb'ed
 
Sounds like your running slightly lean. The carbs drying out can leave deposits that can affect your jetting. Try a dose of Seafoam carb cleaner. If that doesn't work, open your idle jet screws 1/2 to a full turn.
 
sounds to me like carb problem.

BTW, when the bike is cold its suppose to be unresponsive especially if its carb'ed

thank you. I feel MEGA relieved to hear that the unresponsiveness is normal on cold carb'd bikes.

And gav.man thanks also for the help. I dont think the carbs need any adjusting cuz everything else is working great except for that leak on the first start after winter. I will add some seafoam though for extra measure.
 
Your bike leaks gas, has a rough idle, your throttle isn't consistent and you still don't think you need to adjust anything on your carbs? good luck buddy.
 
you need a carb overhaul, because you stored it with gas with 10% ethinal. the pilot circut plugs first.
 
you need a carb overhaul, because you stored it with gas with 10% ethinal. the pilot circut plugs first.
Yep. So many peeps have had probs this spring after storing their bike using fuel with Ethanol in it. The only fuel that doesn't is Shell 91 and Ultramar 91!!!

People says "it isn't bad for the bike" BULL ****! It leaves this super hard varnish type coating on your carb jets, fuel injectors, etc. My friends R6 was running like crap after the winter. He used Sunoco 94 (the worst stuff). It turned out to be a fuel injector stuck wide open! It'd just piss the fuel right out, not a nice spray or anything. He got all 8 of his injectors professionally cleaned and it runs like a champ now. Shell 91 for him from now on!

-Jamie M.
 
Yep. So many peeps have had probs this spring after storing their bike using fuel with Ethanol in it. The only fuel that doesn't is Shell 91 and Ultramar 91!!!

People says "it isn't bad for the bike" BULL ****! It leaves this super hard varnish type coating on your carb jets, fuel injectors, etc. My friends R6 was running like crap after the winter. He used Sunoco 94 (the worst stuff). It turned out to be a fuel injector stuck wide open! It'd just piss the fuel right out, not a nice spray or anything. He got all 8 of his injectors professionally cleaned and it runs like a champ now. Shell 91 for him from now on!

-Jamie M.

How do u know Ultramar have no ethanol?
 
Your bike leaks gas, has a rough idle, your throttle isn't consistent and you still don't think you need to adjust anything on your carbs? good luck buddy.

well it only leaked gas the very first time i tried starting it. I took the gas tank off to take a look, jiggled some hoses around and waited a couple days. Leak stopped completely. no problems there. The idle has gotten much better as well. When i posted this thread, I was still running the tank with fuel stabilizer in it. After finishing that tank and getting fresh gas everything has been working great.

Throttle response is fantastic as well once the bike warms up a bit. But apparently its supposed to be like that on old carb'd bikes?

what exactly does a carb overhaul entail? Just cleaning and syncing?
and thanks for the info. I didn't know ethanol was so bad. Guess im going to shell from now on.
 
How do u know Ultramar have no ethanol?
Is that a serious question? Lol, I asked them:

Ultramar said:
From: Ultramar ginthomeheat@Ultramar.ca
Sent: Friday, November 04, 2011 11:11 AM
To: toysareforboys.com
Subject: Ethanol in your fuels? [<AD23721>]

Hello,

Provincial law requires us to sell a certain percentage of ethanol in our gasoline.
Ultramar has limited this percentage (approximately 10%) to regular gasoline only. The mid-grade (Plus) gasoline, in some station, is equipped with a system that mixes the Regular and Supreme to create the Plus grade of gasoline, rather than having a seperate tank for the mid-grade. As for the Supreme gasoline, it contains no Ethanol.

Therefore you could receive some ethanol in certain stations if you purchase the Regular or Plus gasoline.

Best Regards,
Marie-Anne Prenevost
Ultramar ltee
Service à la clientèle
Customer service

I was having problems with ethanol and Nitrous (not in my bike) and e-mailed every single company about Ethanol. Shell 91 and Ultramar 91 were the ONLY fuels that contained no Ethanol :(

-Jamie M.
 
Is that a serious question? Lol, I asked them:



I was having problems with ethanol and Nitrous (not in my bike) and e-mailed every single company about Ethanol. Shell 91 and Ultramar 91 were the ONLY fuels that contained no Ethanol :(

-Jamie M.

I was serious. Thanks for confirming.
You get better mileage without Ethanol
 
I was serious. Thanks for confirming.
You get better mileage without Ethanol
Yep, it's true! I confirmed 6% better fuel economy on Shell 91 vs. Petro 91. This is with switching tank after tank over 15,000km's on my 08 R6. For the last 25,000km's of her life she only drank Shell 91. I try and use Ultramar 91 whenever possible now, gotta support the little guy ;)

-Jamie M.
 
Yep, it's true! I confirmed 6% better fuel economy on Shell 91 vs. Petro 91. This is with switching tank after tank over 15,000km's on my 08 R6. For the last 25,000km's of her life she only drank Shell 91. I try and use Ultramar 91 whenever possible now, gotta support the little guy ;)

-Jamie M.
Hmm, Shell 91 you say! I should give it a try, till now ive only been using petro's 94, and ive had ZERO problems with it, even while winterizing my old scoot. But better fuel economy? sounds too good to be true, but ill c for myself tomorrow (my tanks only got about 2L left in it) :P
 
Hmm, Shell 91 you say! I should give it a try, till now ive only been using petro's 94, and ive had ZERO problems with it, even while winterizing my old scoot. But better fuel economy? sounds too good to be true, but ill c for myself tomorrow (my tanks only got about 2L left in it) :P
Petro 94 has lots of Ethanol in it = bad bad bad. If you can find a Petro station that DOESN'T sell 94, their 91 is safe to use (no ethanol).

Why are you using premium in it? Your user manual calls for 87 octane, and by running premium you're not only wasting money, you're possibly losing power and fuel economy (higher octane fuel is harder for your lower compression engine to ignite!).

Unfortunatly I don't think you can find 87 anywhere without ethanol, but if you've been running 94 with ethanol and were happy with it, running 87 should blow your mind and save you some serious $$ at the same time! :)

-Jamie M.
 
When you got the bike last year did you ride it at all or did you just store it? If you rode it, how was it then?

Although it appears you do have issues with the carbs. I wouldn't start there. The maintenance history of the bike appears to be unknown therefore I would first check the valves and ignition timing.

First check / adjust valves and Check ignition timing

If all is good there then focus on the carbs

Read the Troubleshooting Section (Section 20) - Poor Performance at Low and Idle Speeds
http://dc384.4shared.com/download/_Y3eGfeo/Honda_CBR_600_F2_91-94_Service.pdf

Valves with incorrect clearance can cause the symptoms you are seeing.
Also, syncing the carbs when the valves are out of spec is a waste of time.

If you are not mechanically inclined bring the bike to a mechanic or someone who is. Cost will mostly be labour if there are no major issues, and will vary between shops. ** Make sure to get a quote **

Valve clearance in the manual (link above) is on page 3-5

Valve Adjustment Guide- CBR 600 F2/F3

http://cbrforum.com/forum/stickies-91/valve-adjustment-guide-101969/
 
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OK, Ethanol & gasoline 101.

Ethanol is used in fuels for 2 purposes, to bump up the octane level and also to burn cleaner. Alcohol burns with a clean blue flame. But it is less energy dense, meaning, there is more energy per 1L of gasoline than 1L of ethanol. In short you will get more mileage from pure gasoline than a mixture with ethanol.

Gasoline is made up of a mixture of hydrocarbons. Other ways of increasing octane levels is branching the molecules in gasoline (expensive way) and adding lead that attaches to the molecules in gasoline (cheap way, but is banned in ontario). Those methods mentioned, increases the octane by:
1) Lead- Attaches to the molecules of the gasoline, basically anchoring it, making it sluggish. Because detonation is hampered by it not being overly active.

2) Adding branches in the molecule - this causes the gasoline molecules to have less surface and burn much slower. The branches add bulk to the molecule. Think of a cigar burning slower than a cigarette.

And yes, I'm a nerd
 
OK, Ethanol & gasoline 101.
Thanks for the info :) When I was at the drag strip I saw some guys filling their tanks from a gas can (asked them, fresh Shell 91), then dumping in some paint thinner!!! I asked them what it was, they said Toluene, $15 for 4L! I asked him why, he said "he's running 15:1 compression". If alcohol contains less energy than gasoline, how does Toluene rank up there? Wouldn't it be a better additive than ethanol?

http://www.homedepot.ca/product/toluene-378-l/912204

-Jamie M.
 
Thanks for the info :) When I was at the drag strip I saw some guys filling their tanks from a gas can (asked them, fresh Shell 91), then dumping in some paint thinner!!! I asked them what it was, they said Toluene, $15 for 4L! I asked him why, he said "he's running 15:1 compression". If alcohol contains less energy than gasoline, how does Toluene rank up there? Wouldn't it be a better additive than ethanol?

http://www.homedepot.ca/product/toluene-378-l/912204

-Jamie M.

I would say it has more energy than ethanol or even gasoline. I would assume it has a higher oct. number because the molecule exist in a ring. For it to combust, they need to break that ring first.

Just a bit of side info, Toluene is used to make TNT
Thanks for letting me know where I can find toluene, lol
 
I would say it has more energy than ethanol or even gasoline. I would assume it has a higher oct. number because the molecule exist in a ring. For it to combust, they need to break that ring first.

Just a bit of side info, Toluene is used to make TNT
Thanks for letting me know where I can find toluene, lol
Very very interesting. I'll have to make sure it's not on my probation list of "chemicals not to possess", I know hexamine is on there ;)

I'm going to be running a dual map switch on my girlfriends 09 R6, and read that straight Toluene is 114 octane, so should handle some extra ignition advance nicely Can't wait to try some!

I wonder how hard on the fuel system it'll be, o-rings and the like.

-Jamie M.
 
Very very interesting. I'll have to make sure it's not on my probation list of "chemicals not to possess", I know hexamine is on there ;)

I'm going to be running a dual map switch on my girlfriends 09 R6, and read that straight Toluene is 114 octane, so should handle some extra ignition advance nicely Can't wait to try some!

I wonder how hard on the fuel system it'll be, o-rings and the like.

-Jamie M.

LOLz, list of prohibited chemicals, eh, lol. I'm surprised u can find it in a home hardware store.

Are there mechanical modifications you have to do for it to work?
 
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