Fuel

[Merlin]

.......no problem,why try to enlighten those that wish not to be??......

[Mick Milakovic]

As I said earlier in this thread, I've been using Specto synthetic in my bikes the last 3 years with good success.  Is Specto another brand of Golden Spectro?

[Rain Man]

I always liked to use the cheap stuff and jetted the engine that way.  The simple reason being that Netra always runs fuel stops into these poor Mom and Pop convenient stores with 6 month old 93 octane, so the bike runs like crap the rest of the Enduro anyway !!   Theres got to be a happy medium.   heck running tired fuel sure beats pushing the dang thing up a hill !!  
  The things we do on sunday...

Raymond
 Down East Pentons

[DKWRACER]

Sorry Steve, I meant to say that I do not, shy away from that mixture.
But this post brings regional concerns, to be shared amongst friends.. Gas is gas, but then again, maybe it's not...Tom...

[john durrill]

Steve,
 Do the bike shops around you carry the Maxima Super M?
It works well with pump gas. Dwight recommended it to us for our small bores and it has held up well in both the 175 KTM engine of my sons and my 175 hybread.
I had very good luck with 100 LL on the 79 400 we restored in 91 and Knudson was using it in the 250 that was doing so well in the nationals. I added an extra base gasket on the Piner of my sons so we can use pump 93 oct. I could not tell any difference in performance on his 175 with the extra .010 gasket other than it was a little easier to start
Chuckle chuckle!
 I'm at sea level + 183 feet( highest point around here) and had no fuel boiling problems in in the summer (90 + degs and 90+ humidity). Unless I was flat tracking or Road Racing I would add an extra Base gasket and use pump gas. Its a whole lot cheaper and we don' t notice any difference in the woods. The bike runs cooler , it's easier to start and it should last longer.

[brokenb23]

Can not resist this. Probably the best tested premix oils are your outboard motor oils.I have used them for years and never had any problems.  I have had problems with some of the so/so trick oils.  
Bob Brizzee

[James]

While I prefer another oil, I can attest that Bob's bikes run quite well...especially that 250 Mc5-it is a particularly stong one.

  On the fuel note-Lynn Shoup has recommended 100LL and run it for years. Mike Helper has run it for 30 yrs. We discoverd Saturday that the Castor 927 was separating with the av gas. I am now using Golden Spectro at 50:1 and have jetted bike accordingly.

You can adjust with jetting and timing your bike to run on either, pump gas, av gas or race gas. The best thing about the av gas is that it is low lead- 100 oct, very consistent and inexpensive.
Also, at 100 oct the jetting is not far off pump gas jetting.
 I have run pump and race before. Usually the pump worked fine-sometimes I had a bike that liked the race gas better-more timing leaner jetting. The air cooled open bike is one i had not encountered til now-so this is what I have found out so far with it. James

7" and 4" travel? Hmm-that makes 11" Hey! I can live with that.

[Rocket]

Call me cheap, but I have been using Pennzoil outboard motor oils for better than 20 years, never had an oil related faliure.  I try to use Shell 93 octane unleaded gas.  Pennzoil burns very clean, no power valve problems in my 200 KTM with carbon build-up.
Rocket

[firstturn]

OK you ask for it.....CHEAP[^].  Man this has been a long time coming since that comment about "two things come from Texas, Steers and $#%%#$".  And as we say in Texas "every Dog has his day" I know I have had plenty.  Thanks for the opening Big R.[)]

Ron Carbaugh

[john durrill]

James, Steve
 I think the kind of oil you use with LL is the key. Some oils may not work well at all with it. We have used Spectro since the early 70's and it has always done a great job with the small bores mixed with any gas we used. We switched the Maxium Super M because we are running super trapp spark arresters and spectro gums them up quicker than some of the newer oils.
 John D.

[Dwight Rudder]

quote:Originally posted by James

While I prefer another oil, I can attest that Bob's bikes run quite well...especially that 250 Mc5-it is a particularly stong one.

  On the fuel note-Lynn Shoup has recommended 100LL and run it for years. Mike Helper has run it for 30 yrs. We discoverd Saturday that the Castor 927 was separating with the av gas. I am now using Golden Spectro at 50:1 and have jetted bike accordingly.

You can adjust with jetting and timing your bike to run on either, pump gas, av gas or race gas. The best thing about the av gas is that it is low lead- 100 oct, very consistent and inexpensive.
Also, at 100 oct the jetting is not far off pump gas jetting.
 I have run pump and race before. Usually the pump worked fine-sometimes I had a bike that liked the race gas better-more timing leaner jetting. The air cooled open bike is one i had not encountered til now-so this is what I have found out so far with it. James

7" and 4" travel? Hmm-that makes 11" Hey! I can live with that.

I crashed an WWI Aeroplane due to 927 Castor separation in AvGas.  AvGas is highly not recommended for race fuel. It is designed for a relative low compression, low steady rpm , at higher altitudes. It is extremely high in Lead content. Much higher than MoGas ( auto fuel ) ever was.
You can have good luck mixing a couple gallons of AvGas to 3 gal of Mogas to make a higher octane fuel ( about 97 to 98 oct.) you don't need more than this. Use Maxima Super M.  Mixes well and doesn't separate, burns clean. It just doesn't have the Castor smell. Just don't use straight AvGas.  Too high an octane will cause the engine to run flat. Also AvGas can fool you. It will look like you are running rich but you will be lean.  Beware.
Cher'o,
Dwight

Dwight Rudder
7 time ISDT / E medalist
8 time National Enduro Class Champion.