My carbed 900 hates Shell 98 fuel in that I get regular carb flooding when I use it. This has been a consistent pattern. I use BP or Caltex 98 and the problem clears up. There must be a pretty bloody waxy additive that gets under the float needles that the carbs don't like.

How do the injected bikes go with it?

I try the Shell every now and then coz I have the dockets, but the same flooding problem every time. I have called Shell about this problem and the rough running down low some people have complained about. I spoke with a Shell engineer, it was interesting.

Should we have a seperate fuel thread for this?

Quote from: Two dogs on January 08, 2012, 09:30:37 PM
The dealer I bought mine from told me to only use Shell............ if I was out of fuel and couldn't get anything else 
complete contrast to above post , they told me Shell had additives that 2V engine didn't like.

Its a conspiracy I say ............ 

Yeah, thats what I thought as well, needless to say I haven't followed his recommendation.

My carbed 750 will NOT run on anything above standard swill of ANY manufacturer!!

It fouls plugs and runs like a bucket of shit!! 

Runs perfectly on 91!! 

Dont use Shell much as there arnt too many around these parts! Caltex, Mobil and the Independents around here!!

Standard comp would be pretty low, so you wouldnt need 98. You'd save a few bucks.
Mines got hi comp pistons so Ive gotta use 98 ot it'll ping.

Quote from: koko64 on January 08, 2012, 10:55:23 PM
Standard comp would be pretty low, so you wouldnt need 98. You'd save a few bucks.
Mines got hi comp pistons so Ive gotta use 98 ot it'll ping.

Heh, the 7fiddy's comp is so low it could probably run on Kero!? 

Yeah got my 1100evo from Fraser's, the handover mechanic said premium 95.  His reasoning was a slightly higher comp than previous new gen models. The manual also indicates 95. Also Id love to know what other additives go into premium fuel from brand to brand (shell, bp, caltex etc) to warrant a bike manufacturer to recommend one 95 fuel over another. I know some diesel fuel have detergent additives to prevent glazing, are the additives for premium fuel something similar? Hmmm it's a bit like having MSG added to your Chinese take out....taste great but you don't know what the long term effects will be

from what i've been told by people in the industry, i think there's only two refineries in aust that make premium across all the brands, so it's a generic formula with specific additives for each brand.

the additives are very specific.  a mate of mine went to work at mobil after uni and a mate of his went into premium production control.  they test the octane of the batch at the end of each shift and they can tell by the octane number how much too much of the additives they added for the shift and how much that has cost them.  the additives are the expensive stuff.

Quote from: dragonworld on January 09, 2012, 12:33:47 AM




Heh, the 7fiddy's comp is so low it could probably run on Kero!? 

Hmm, need high comp for kero.  It's like diesel.  I've seen guys run JetA1 in their 4WDs.

Quote from: Sundog on January 08, 2012, 09:19:29 PM
Fraser's told me at my last tune-up that Ducati had worked with Shell on the formulation of their V-Power fuel and that was what was recommended, at least for the more modern fuel-system Ducs, it was the first I heard of it.

Smells like a commercial arrangement to me.  The "use Shell oil only" sticker on the crankcase gives me the same impression.

My '02 runs fine on 91 RON and even better on 95.  95 is what's recommended in the owner's manual.  Gives slightly better mileage too.

Quote from: suzyj on January 08, 2012, 11:51:14 AM
My understanding is that the ethanol in E10 is hydrophilic, so binds with water in the air.  The water then gets absorbed by the nylon in the tank, making it swell.  Thankfully it's a reversible process, but it's really irritating to have to drain and disassemble the tank periodically to shrink it.

What I don't understand is what's the deal with higher octane fuels (which don't contain ethanol). I fill my monster on 91 unleaded when I can get it, and 95 when I can't get 91.  I'm not sure if I can tell much of a difference, to be honest, though I did get a crappy batch of 95 from the Shell at Eastern Creek, that left my monster running like a bit of a dog for a week

Exactly.

The issue is water, which occurs in gasoline as a contaminant.

You will only see this issue in tanks marked "PA6" on the bottom, for "polyamide 6" also known as Nylon-6.

Nylon-6 absorbs water up to 10% volume.

If you get some expansion, drain the tank dry.  Tanks with minor deformation will shrink back.

On the older monsters with the full trellis frame, pay close attention to the black bumpers on the bottom of the tank which sit on the frame.  Those will tell you how badly it's deformed.  The tank can also deform long-wise and press against the keyswitch. 

In the US, there are epoxy tank coatings which work.  You have to make sure to find a compatible one and prep the tank correctly (esp if its had gasoline in it).  You have to dry it completely and wash all of the gas out before coating it.  Also, the surface of the material inside the tank can have air bubbles which can prevent adhesion by the coating.  You have to cut these open..  They are essentially pimples with a VERY thin top.  On mine, I cut a big slit into them and then cut off some of the top.  The coating when inside and bonded very well with the surface inside.

There are MANY different epoxy adhesives which can work, but they need to be compatible with polyamides.  Some are less so.  The main issue is preparation, which is tricky with these tanks, but with patience and effort it can be done well.

Quote from: brad black on January 07, 2012, 01:56:46 PM
well, if someone can tell me how you tune an engine to suit a certain fuel i'd give you an answer.  i've never found anyone who can actually tell me what you do to tune for super vs unleaded (like i used to get told to do in the old days) or tune it to 95 over 91.  no idea.

You need to adjust the compression ratio up or down...

intentionally-misunderstanding-big (More realistically, you can run more ignition advance if you can guarantee high enough octane)

If anyone has a problem with a swollen tank. I have a brand new, never used, matte black tank you could buy.