| Author | Message | ||
     Ryker77 |
For a tuber with high compression and larger cam... I belive my twintec igntion is at 18 BTDC. Timing is something I undertand the basics about but not the fine consept of tuning around it. What is the maxium timing retard for the v-twin? At what point does power get effected? | ||
| Ryker77 |
Purpose-- is to run pumpgas with octane booster. Then if (never do - bought the bike this way) wanted to run the strip I could adjust timing and dump in the high dollar fuel. Sometimes I get some pinging at lower rpms with a good amount of throttle applied. | ||
| Firemanjim |
I'd adjust it just like we used to do our V-8's, back it off til it stops pinging. | ||
| Ryker77 |
Kinda looking for more of techincal reason. And I don't want to "cure" the pinging by placing the engine in danger or loosing performance. | ||
| Fullpower |
"Sometimes I get some pinging at lower rpms with a good amount of throttle applied." high compression aircooled engine on the street WILL do that. the only solutions are to either run a LOT higher octane fuel, or DONT TWIST THE THROTTLE hard at lower rpm's. other than longer cam timing ( more overlap) or lower mechanical compression ratio you will have detonation. ignition timing retardation will only make the exhaust valve and seat area hotter, thus negating any advantage of later spark. My "solution" was to carry a gallon of methanol around to spike my sportster's gasoline when far from home. But what we really need to do is run a much longer duration cam set, and try to get cranking compression down to around 180 PSI or thereabout. | ||
| Ryker77 |
I run high octane pump gas with a dose of Lucas "offroad only" Octane booster. So I should be around 95-97 octane. Couldn't find any better octane booster other than gallons of ethanol / methanol.. How much octane does a gallon of methanol have and whats the cost? I mostly ride causally. I run the larger 1qt oil filter and today I found a 7" long filter that holds 2 qts so next oil change I'll try that. It rained on the way home today and was alot cooler. No pinging.. | ||
| Slaughter |
Don't even try methanol. Jetting or induction isn't going to translate. Methanol will TRASH almost any material used in your fuel system. Plastic, seals, most types of steel, aluminum - all can be trashed by methanol. Even if everything was OK, it's gotta be tuned to burn about 30% more fuel. | ||
| Trac95ker |
Why don't you try a plug with a cooler heat range. | ||
| Teeps |
Toluene works as an octane booster. I run 8 to 10oz. per gallon of 91 octane pump gas. | ||
| Slaughter |
Buy race gas for racing! Taint that expensive when you consider everything else such as proper tuning, possible other problems associated with odd combustion characteristics. Get some 100 unleaded and just go with it. | ||
| Firemanjim |
Champion makes a bunch of cooler plugs, had to do that on my motor in my S-2 along with retarding timing and rejetting my pilot jet twice--Mikuni. | ||
| Glitch |
Listen to the Fireman, he knows of what he speaks. | ||
| Hughlysses |
You aren't going to damage the engine by retarding the timing unless you get it ATDC, in which case you'll be blowing still-burning gases out of the headers, burning valves, etc. | ||
| Ryker77 |
Why don't you try a plug with a cooler heat range. done it allready. Running the coldest Champion made. Toluene works as an octane booster. I run 8 to 10oz. per gallon of 91 octane pump gas. I think toluene is what some octane booster are? Does toluene evaporate over a time period? whats the cost? Buy race gas for racing! Taint that expensive when you consider everything else such as proper tuning, possible other problems associated with odd combustion characteristics. Get some 100 unleaded and just go with it. I don't race now and probably never will. Looking for good street options for fuel and for a engine tuning guru to tell me what timing adjust they have run before. You aren't going to damage the engine by retarding the timing unless you get it ATDC, in which case you'll be blowing still-burning gases out of the headers, burning valves, etc. I understand the basics of engine timing and could figure that much out. Looking for an engine tuner to tell me they have tuned a bike to run X BTDC or that never go beyond X BTDC. | ||
| Teeps |
Ryker77 Posted on Saturday, June 23, 2007 I think toluene is what some octane booster are? Does toluene evaporate over a time period? whats the cost? Yes, some OTC boosters list toluene as an ingredient. I suppose toluene does evaporate, how quickly it leaves from a tank of fuel, I don't know. I pay $10 a gallon, for toluene, at local house paint store. | ||
| Firemanjim |
Are you sure about that Champion --what is the plug number as I found some real cold ones for the nitrous set up I had. They have several grades available,look here http://www.championsparkplugs.com/search_char.asp? threadSize=12mm&hexSize=&gap=&seatType=gasket&term inalType=&heatRange=&reach=19mm+%283%2F4%22%29&res istor=&action.x=51&action.y=8 Vallejo was running the A 59 and 57's in their racebike, I used the 57's and some NGK racing plugs that corresponded to a 55. | ||
| Firemanjim |
Look at this chart showing hot to cold heat range for Champion plugs, the recommended plug for a Buell is a RA 4HC,it is the hottest one on the chart in that type plug.You can see the A type racing plugs go WAY colder. http://www.cvproducts.com/cv/technical/sheets/spar k/Champion.pdf | ||
| Slaughter |
Most major metro areas have a few places that sell street-legal race gas (unleaded) in bulk. Right now, we can get VP 100 unleaded for $4 per gallon and it's street legal. There are EPA fines for burning toluene outside of a race track in CA (can't speak to the other 49 states though) Nice here in CA since the highest octane nearly anywhere is 91. | ||
| Teeps |
Where do you find VP100 for $4 a gallon? | ||
| Slaughter |
We've got it at Willow Springs - that's the retail price. Sunoco also has 100 unleaded at some stations. | ||
| Ryker77 |
Fireman, thanks a bunch for that link. I've been running the ra4hc. And now have options to go much colder. I'll work my way down that list and try ra2hc. | ||
| Ryker77 |
toluene is a good trick - http://www.europeancarweb.com/tech/0503ec_octane_b oosters_tested/photo_11.html | ||
| Tattoodnscrewd |
With my new top end (on my S1) I am now mixing a gallon of race gas (110 octane here- available at a regular gas station right down the street) with regular gas at every fill up ... I was also noticing pinging at low rpm - mostly in 3rd to 5th gear ... after mixing the race gas in I don't believe I have noticed much pinging at all .. Just because you don't race, doesn't mean you can't use race gas .. at $5.50 a gallon it doesn't really hurt , I am tempted to go buy a 5 gallon gas container and fill it up and just drop a gallon in at home before I go fill up ... | ||
| Ryker77 |
Heck I'm lucky to even find a gas station open past 10pm. Living in Southern WV is like the 1950's. Not much around - no race gas, not much crime, no illegal aliens. I buy my b100 biodiesel when I pass though Ga or NC 5 5gallon jugs at a time. So I guess I should buy some gas jugs and locate some race gas. I don't care about the cost that much. |
