Author Topic: Motorcycle jetting for alcohol  (Read 17588 times)

0 Members and 1 Guest are viewing this topic.

Offline Sequim Jim

  • Jr. Member
  • **
  • Posts: 48
Motorcycle jetting for alcohol
« on: March 30, 2017, 07:59:18 AM »
I'm sorry if this has been discussed but I can't find any information to confirm my jetting problem.
I built a turbocharged Yamaha R1. Originally I planned to run C12 but became worried I would start pinging at higher boost. So far I haven't find a way to retard my timing.
My next option is E85 to alcohol. My current main jets in my Mikunis are 130s. My idle jets are 15s. I've been told to start with 180 for the main and leave the bottom end alone.
Is this correct? I have a AEM AFR gauge to find tune my fuel ratio, I just need a starting point.
Best regards
Jim

Offline RansomT

  • Sr. Member
  • ****
  • Posts: 559
Re: Motorcycle jetting for alcohol
« Reply #1 on: March 30, 2017, 11:47:44 AM »
A good starting point for Ethanol (E85) is 30% more fuel above what you would use with C12/C16.  Typically, you also want a touch lower reading using the gas scale with Ethanol.  e.g. If you like running 11.5:1 with C12 on boost, then target 11.3:1 with E85.

I also would highly recommend running a race grade "E85".  The best I have found is Ignite race fuels.  They make a 114 octane (Ignite Red) that is 90% ethanol.  Cost is also less than the big names, if you can find a local distributor.

Offline edinlr

  • Sr. Member
  • ****
  • Posts: 344
Re: Motorcycle jetting for alcohol
« Reply #2 on: March 30, 2017, 12:59:11 PM »
Jim, check to see if any of the ignition modules that Dynojet will help.  I have one for my H2 Ninja but have not set it up.  The Kwack's internal sensors will detect knock in a matter of a few rpm and start taking out timing in 2 degree increments until the problem stops and then start adding timing back in.  Ideally you would want something that backs timing off as boost increases, but second best might be to have the timing retard at a certain speed and monitor the settings on the dyno.  With as many people on the forum who run turbos, there has to be a pretty standard solution besides just adding octane.
Honda CX650 turbo, Kawasaki H2 Ninja, Kawasaki ZX750 turbo

Offline maj

  • Sr. Member
  • ****
  • Posts: 743
Re: Motorcycle jetting for alcohol
« Reply #3 on: March 30, 2017, 04:35:49 PM »
Jim it may be easier to go EFI with a simple standalone
jetting can have you pulling the carbs so many times its not funny anymore , although i know the R1 blow thru setup is well documented and there are many examples of easy fit and use the E85 opens another can of worms

BTW if you dont mind some thoughts on your bike setup
I would put the fuel tank behind the plenum so you can get lower and reduce your screen height
route the up pipe elsewhere so your leg is in tight , is it going to ice tank in rear ?
carry an alternate version cut down tail with less side area in case of handling problems or side wind 

Offline generatorshovel

  • Sr. Member
  • ****
  • Posts: 412
    • http://www.dlra.org.au/forum/viewtopic.php?t=556
Re: Motorcycle jetting for alcohol
« Reply #4 on: March 30, 2017, 05:31:11 PM »
I've been flogging the methanol/supercharger dead horse combo for 5 years now Jim, & I'm "nearly there"
Maj is right, EFI is the way to go, but, if you're as stubborn as I, you will sort carbs out, eventually, although my setup is draw thru, the a/f needs are the same as blow thru.
Start with at least +2.2 times more fuel than you would need with gas,,,+ 2.5 is safer, this includes ALL jets, not just the main jets, make sure the needle jets are at least .001" larger than your mains.( there's quite a bit of math involved in calculating needle / needle jet sizes)
Remember,,a methanol engine that runs fine during test runs will run the risk of lean out as the cylinder head temp increases, and excessive heat & lean mixture = detonation,(I hope you have good piston stocks)
Heat is forced inducted engine's enemy, intercooling makes sense to overcome that, but with that (& carbs) methanol tends to drop out of suspension,
O2 sensors don't like methanol either (unless you use expensive ones) & tend to tell lies until you get the mixture "right"
 A byproduct of methanol burning, is water, especially on initial start up, water kills O2 sensors.
Plug reading is the best way to find out why your engine died, not if it will die,,as is egt reading, but it all helps to get you there.
Enjoy,,,,,,
Tiny
Tiny (in OZ)
I would prefer to make horsepower, rather than buy, or hya it, regardless of the difficulties involved , as it would then be MINE

Offline Sequim Jim

  • Jr. Member
  • **
  • Posts: 48
Re: Motorcycle jetting for alcohol
« Reply #5 on: March 31, 2017, 08:31:40 AM »
Thanks everybody.
I tried finding a EFI for my bike (2001 R1 20 valve) and didn't have any luck. I contacted every ignition company and the only solution was to build a sliding/rotating plate for my ignition sensor.
I hired an electronic engineer to design a device that electronically retarded the timing and it failed.
As for the tank. I'm 6'4", so the tank height was set as the lowest I could get and still be comfortable. The icebox is behind my seat and the battery mounted ahead of the rear wheel on the swingarm. This helps balance the bike. Because I'm so big, most of my weight was up front. About 70% of the bike/rider total weight on the front wheel. I was afraid of losing traction. The seat area allows me to move back and forth several inches, to help balance the bike as needed.
Best regards
Jim

Offline Sequim Jim

  • Jr. Member
  • **
  • Posts: 48
Re: Motorcycle jetting for alcohol
« Reply #6 on: March 31, 2017, 08:37:25 AM »
Here is the naked version of my bike.
Best regards
Jim

Offline wobblywalrus

  • Hero Member
  • *****
  • Posts: 5503
Re: Motorcycle jetting for alcohol
« Reply #7 on: March 31, 2017, 09:45:05 AM »
Some carb makers have alcohol kits with all of the little parts.  Years ago I installed one.  There were a lot of things in the kit besides jets.  It was either a Mikuni or Keihin carb.  Sudco should have what you need and they have an on-line catalog.  It is important that the fuel tank breather, needle valve, and pet cock can handle the flow.  It is more than a simple jet change.

Also, a clear gas line was installed that ran from the bottom of the float chamber and went up alongside the float bowl.  It had an open end.  The height that gasoline was in it was measured.  Then, the alcohol gas mix was used.  The float tang was bent a little bit so the height of alky mix in the tube was the same as it was with gasoline.  Then the tube was taken off.  It was only used to reset the float height. 

Offline TheBaron

  • Full Member
  • ***
  • Posts: 122
Re: Motorcycle jetting for alcohol
« Reply #8 on: March 31, 2017, 09:54:02 AM »
I hope that you don't think that methanol will cure all your detonation issues,,, it will NOT....

Methanol is equal to about 116 octane .....and it will detonate horribly if pushed too far......

I've messed with supercharged motors for a long time, and the longevity  key is to keep the dynamic compression ratio and the spark timing under the fuel's stability limit.

Big Big Questions: what is your target boost pressure and what is the static compression ratio of the engine????

I currently run a carbureted supercharged air-cooled pushrod twin on gasoline.... It doesn't get any more difficult managing the thermal issues...

Smitty




Offline Sequim Jim

  • Jr. Member
  • **
  • Posts: 48
Re: Motorcycle jetting for alcohol
« Reply #9 on: April 01, 2017, 09:28:49 AM »
I replaced the stock pistons and conrods with CP Carillo 10 to 1 turbo pistons and h-beam conrods. I removed the factory head stubs and installed longer, stronger head studs. The valve springs are designed to handle 35 lbs of boost. My cam timing is 114 degrees. I have a Magnaflow fuel pump and regulator. The bike is running on 10 lbs of boost. I'm hoping for 25 pounds.
Best regards
Jim

Offline TheBaron

  • Full Member
  • ***
  • Posts: 122
Re: Motorcycle jetting for alcohol
« Reply #10 on: April 01, 2017, 12:11:25 PM »
OK Jim,,, this looks doable but you should know know how close to the limit you will be....

In order to calculate your dynamic compression ratio I need to know:

Connecting rod length and when the Intake valve closes after BDC,,,   (on seat and at .040"  is best)

 Is the 114 degrees overlap ?

If your ECU has spark knock sensing w/auto retard you have an easier safer path forward...

Smitty

Offline Sequim Jim

  • Jr. Member
  • **
  • Posts: 48
Re: Motorcycle jetting for alcohol
« Reply #11 on: April 02, 2017, 09:34:57 AM »
I'm sorry I didn't keep the paperwork that came with the conrods, so I don't know the length of the rods.
Here are my notes for cam timing that came from Hurricane Performance in Canada (this company builds 700+hp snowmobiles based on the R1 engine). Hurricane supplied most of my parts and gave some build advice.
Intake
Valve opens 1mm at 3 degrees Before Top Dead Center. At 51 degrees After Bottom Dead Center it is closing but is open 1 mm. That should equal 114 degrees overlap.
Exhaust
At 50 degree Before Bottom Dead Center the valve opens 1 mm. At 2 degrees After Top Dead Center the valve is closing but is still open 1 mm. That equals 114 degrees.
When I changed the valve timing I used a slotted cam gear. The movement was unnoticeable to my eye but the cam timing wheel made it easy to a point. The bike started right up with a little bit of choke and ran pretty good on 10 lbs of boost with auto gas.
« Last Edit: April 02, 2017, 09:49:48 AM by Sequim Jim »
Best regards
Jim

Offline Sequim Jim

  • Jr. Member
  • **
  • Posts: 48
Re: Motorcycle jetting for alcohol
« Reply #12 on: April 02, 2017, 10:21:45 AM »
Found the conrod information.
Yamaha YZF-R1 98-03
Stock rod length is 110.50mm

Part Number Type Bolt Size Length PE Width BE Width BE Bore Pin Dia
YA-YZF>1-8M4350S PRO-H 8mm CARR 110.50mm 18.03mm 20.80mm 39.014mm 17mm
Best regards
Jim

Offline TheBaron

  • Full Member
  • ***
  • Posts: 122
Re: Motorcycle jetting for alcohol
« Reply #13 on: April 02, 2017, 11:07:57 AM »
Got it !

I'll run the numbers and get back to you....

Smitty

Offline TheBaron

  • Full Member
  • ***
  • Posts: 122
Re: Motorcycle jetting for alcohol
« Reply #14 on: April 02, 2017, 09:09:38 PM »
The numbers are as follows :

4500' elevation, 25 psi boost, gives a 20.98:1 dynamic compression ratio at the torque peak

6000'    "            "    "     "        "     " 20.17:1     "              "              "    "    ""     "       "

7500'    "            "     "    "        "     " 19.36:!      "              "              "    "     "      "       "

4500'                 15 psi                      15.70:1
 
7500'                   "   "                       14.49:1

I think I'd go with 15 psi of boost, and test very carefully from there.

I'm running 12.4:1 Dynamic CR with 116 octane race gas  in a hot running (400 degree F) air-cooled motor and I get a bit of detonation when the race gas gets the least bit old and stale. My static CR is 8.4:1 and I run with of 12 psi of boost...

If you want to make really high boost with big HP numbers,,,,, drop that static CR to 7:1 and run chilled water in your intercooler ,,,,

Note: at the HP peak the dynamic CR will be 8% to 15% lower than at the torque peak due to less cylinder fill time at higher rpm.

Boost pressure is not the end-all be-all of making power,,, Cubic Feet of Air being processed is...

An Engine that breathes very well can make more power with 7.5 psi of boost than another less efficient engine with 12 psi of boost...

Keep in mind that at the Drag strip, motor can tolerate a lot more compression for a few seconds than engines running flat out for mile after mile...

I hope some of this helps you get going with that Yamaha 5-valve...a great little motor....

Good luck and ride safe,

Smitty