Gas in a Hawk

Alpha Reign · 09-28-2018, 10:10 AM

I recently put higher octane gas in my Hawk 250. Before I was using the lower octane. Is there any benefit in using higher octane gas?

Red Hawk · 09-28-2018, 10:22 AM

NO
But you may feel better inside by buying the best.. Unless you have high compression or advanced spark it will do nothing. Higher Octane burns slower so your flame spreads and pushes the piston down slower.

Lower Octane burns Faster so it slaps the piston and you hear the knock.

Go and find the stuff NOT laced with corn ethanol and that will be a kind jester to your engine. Alcohol separates with time,, Don't run your bike for a few weeks and you'll find your unwittingly running it on alcohol (Bad for air cooled engines) till you hit the real stuff left in the tank and it pulls the moisture from the air witch settles in the tank and carb, More bad stuff happens.

Biker_Andy · 09-28-2018, 10:28 AM

Premium gas typically doesn't have ethanol which over time can gunk up your carb so there is that benifit. For that reason alone I need to use premium in my '76 Honda. Ethanol is harder on older motorcycles, newer bikes have ethanol safe O-ring in the carb so they won't be damaged from ethanol like my old Honda will. Performance wise the Hawk is a low compression engine so unless your porting & decking your head the gain in octane will be unnoticeable.

imapdog · 09-28-2018, 11:01 AM

no noticeable changes in performance.
rule i use: if burning through the gas fast? use cheapest.
if keeping gas in tank for a few weeks? use high octane.

my experiences with the fuel lines: higher octane erodes the
insides of the factory fuel lines fast. its best to replace them anyways but if all the sudden you start using high octane keep an eye out for erosion of the lines.

Mudflap · 09-28-2018, 11:12 AM

I've never had a problem using 87 octane with 10% ethanol in any of my bikes or my ultralight. Premium 91 octane also contains 10% ethanol here in Oregon. I drain the tank and carb before long term storage, or fill it with 100 LL avgas. Can't use 100LL with a cat though.

My Lifan 140 pings on 87 octane though so I have to use premium in that one.

Ariel Red Hunter · 09-28-2018, 08:06 PM

Quote:

Originally Posted by Alpha Reign

I recently put higher octane gas in my Hawk 250. Before I was using the lower octane. Is there any benefit in using higher octane gas?

Yes, if it is non-ethanol gas. No if it still has ethanol in it. ARH

roundhouse · 09-28-2018, 10:04 PM

87 all the time in the hawk. I do add lucas fuel treatment from time to time. My bike runs rich and happy. No probs with detonation.

timcosby · 09-30-2018, 09:13 PM

Quote:

Originally Posted by Biker_Andy

Premium gas typically doesn't have ethanol which over time can gunk up your carb so there is that benifit. For that reason alone I need to use premium in my '76 Honda. Ethanol is harder on older motorcycles, newer bikes have ethanol safe O-ring in the carb so they won't be damaged from ethanol like my old Honda will. Performance wise the Hawk is a low compression engine so unless your porting & decking your head the gain in octane will be unnoticeable.

all 3 grade have ethanol unless it is labeled "marine" or no ethanol!

Alpha Reign · 09-30-2018, 09:38 PM

Thanks for the info,

Azhule · 10-01-2018, 10:54 AM

Quote:

Originally Posted by Biker_Andy

Premium gas typically doesn't have ethanol which over time can gunk up your carb so there is that benifit.

Read any and all labels before you buy gas is my recommendation.

That "typically has No Ethanol" in premium all depends on where you live and buy your gas... around these parts, unless noted other wise, all gas will contain UP TO 15% ethanol...

You can find stations that offer "Ethanol free" gas, it is clearly labeled as such and you have to pay a premium for it, sometimes it's only offered in the 85/87 grade

Some stations you can fin something saying "Premium contains a trace amount of Ethanol"... this is because the other grades will still contain Ethanol and the Premium grade uses the same pump as the others... they try to "back pump" any Ethanol laced fuel out of the hose, "re-pump premium" in... and you end up with a "trace amount" of it left over...

Depending on your altitude, I would just use 85 or 87 (85 if above 5,000 feet)... use a good "fuel treatment" meant for "phase separation of water"... Nuetra 131, StarTron, and Sta-bil Marine, is a few products that might help with that issue

ChrisWNY · 10-01-2018, 12:48 PM

The compression on the Hawk is under 10:1 which means it's not a high compression engine and does not require "premium" grade gas to run well. I usually fill with premium only because the tank is a couple gallons and it's like $1 extra to put the higher octane stuff in there but 87 is perfectly fine in the Hawk. Most if not all gasoline in whatever octane rating you see at the gas station has 10% ethanol content unless otherwise noted on the gas pump. Use fuel stabilizer end-of-season and run your engine on it for several minutes to prevent any gumming in the carb or the fuel lines while your Hawk sits and collects dust off-season (if you live in a cold climate like I do).

ben2go · 10-02-2018, 08:23 AM

Quote:

Originally Posted by Alpha Reign

I recently put higher octane gas in my Hawk 250. Before I was using the lower octane. Is there any benefit in using higher octane gas?

No. Use diesel.

Azhule · 10-02-2018, 11:11 AM

Quote:

Originally Posted by ben2go

No. Use diesel.

Only if you want to save a whole lot of $$, and make up a few gallons worth of SeaFoam

https://www.msdsdigital.com/sea-foam-msds

(Diesel/Pale Oil 40 to 60%, Naptha 25 to 35%, ISO 10 to 20%)

kirkallen143 · 10-02-2018, 02:44 PM

I run 87 octane with 10% ethanol in the Hawk, also. I do add some Sta-Bil to all my fuels that I use, @ 1oz per every 5 gallons. It will last up to a year that I have found with no ill effects to the fuel.
I rarely let any engine I own sit for more than a couple of months. I at least start them every month, or so and let them run to get the juices flowing, if ya know what I mean.

Kirk

ChrisWNY · 10-02-2018, 07:54 PM

Quote:

Originally Posted by ben2go

No. Use diesel.

Forget Diesel...if you're gonna roll with the big guns, go for nitromethane, straight up.

09-28-2018, 10:10 AM	#1
Alpha Reign Join Date: Aug 2018 Location: Ohio Posts: 131	Gas in a Hawk I recently put higher octane gas in my Hawk 250. Before I was using the lower octane. Is there any benefit in using higher octane gas?
	0

09-28-2018, 10:22 AM	#2
Red Hawk Join Date: Jul 2018 Location: NEPA Posts: 273	NO But you may feel better inside by buying the best.. Unless you have high compression or advanced spark it will do nothing. Higher Octane burns slower so your flame spreads and pushes the piston down slower. Lower Octane burns Faster so it slaps the piston and you hear the knock. Go and find the stuff NOT laced with corn ethanol and that will be a kind jester to your engine. Alcohol separates with time,, Don't run your bike for a few weeks and you'll find your unwittingly running it on alcohol (Bad for air cooled engines) till you hit the real stuff left in the tank and it pulls the moisture from the air witch settles in the tank and carb, More bad stuff happens. __________________ 2018 Hawk P&P Decked .040 off the head. 17/43 D.I.D. 428, NGK Iridium plug, DeCat, Wrapped pipe, Custom S.S. Muffler core, Nibbi PE30 115/35, L.E.D. Lights, Digital Cluster, USB port, Cutting Bord skid plate, Oil cooler w/ custom CRF oil filter inline, 5Wt fork oil, Rear Shock, CNC Back Rack, 30mm FAT bars, Bark Busters, ProGrips, Adjustable levers, Shinko 700’s lots of Loctite!
	2

09-30-2018, 09:38 PM	#9
Alpha Reign Join Date: Aug 2018 Location: Ohio Posts: 131	Thank You Thanks for the info,
	0

10-01-2018, 12:48 PM	#11
ChrisWNY Join Date: Jul 2018 Posts: 212	The compression on the Hawk is under 10:1 which means it's not a high compression engine and does not require "premium" grade gas to run well. I usually fill with premium only because the tank is a couple gallons and it's like $1 extra to put the higher octane stuff in there but 87 is perfectly fine in the Hawk. Most if not all gasoline in whatever octane rating you see at the gas station has 10% ethanol content unless otherwise noted on the gas pump. Use fuel stabilizer end-of-season and run your engine on it for several minutes to prevent any gumming in the carb or the fuel lines while your Hawk sits and collects dust off-season (if you live in a cold climate like I do). __________________ 2018 RPS Hawk 250cc Mods so far: 1. Mikuni VM26 Carburetor w/#115 main jet 2. 17T/45T JT sprockets 3. JT 428 X-ring chain 4. Air box mod 5. Hawk Digital Cluster 6. Aftermarket IMS shift lever 7. Performance Aftermarket Exhaust 8. 295mm Nitrogen Gas Monoshock, 20W oil front forks
	0

09-28-2018, 10:28 AM	#3
Biker_Andy Join Date: Oct 2016 Posts: 347	Premium gas typically doesn't have ethanol which over time can gunk up your carb so there is that benifit. For that reason alone I need to use premium in my '76 Honda. Ethanol is harder on older motorcycles, newer bikes have ethanol safe O-ring in the carb so they won't be damaged from ethanol like my old Honda will. Performance wise the Hawk is a low compression engine so unless your porting & decking your head the gain in octane will be unnoticeable.
	0

09-28-2018, 11:01 AM	#4
imapdog Join Date: Feb 2018 Location: nashville Posts: 574	no noticeable changes in performance. rule i use: if burning through the gas fast? use cheapest. if keeping gas in tank for a few weeks? use high octane. my experiences with the fuel lines: higher octane erodes the insides of the factory fuel lines fast. its best to replace them anyways but if all the sudden you start using high octane keep an eye out for erosion of the lines.
	0

09-28-2018, 11:12 AM	#5
Mudflap Join Date: Sep 2014 Posts: 1,894	I've never had a problem using 87 octane with 10% ethanol in any of my bikes or my ultralight. Premium 91 octane also contains 10% ethanol here in Oregon. I drain the tank and carb before long term storage, or fill it with 100 LL avgas. Can't use 100LL with a cat though. My Lifan 140 pings on 87 octane though so I have to use premium in that one.
	0

09-28-2018, 10:04 PM	#7
roundhouse Join Date: Sep 2017 Location: N Texas Posts: 706	87 all the time in the hawk. I do add lucas fuel treatment from time to time. My bike runs rich and happy. No probs with detonation.
	0

10-02-2018, 02:44 PM	#14
kirkallen143 Join Date: May 2015 Posts: 84	I run 87 octane with 10% ethanol in the Hawk, also. I do add some Sta-Bil to all my fuels that I use, @ 1oz per every 5 gallons. It will last up to a year that I have found with no ill effects to the fuel. I rarely let any engine I own sit for more than a couple of months. I at least start them every month, or so and let them run to get the juices flowing, if ya know what I mean. Kirk
	0