Safest Fuel for Indian Fours.

[partshunt]

Has anyone have a prefference on fuel grade for these old Indian Fours, 89 Octane or should a lower Octane be more suitable to prevent overheat? It seems the higher the Octane, the slower the burn. Just tryibg to run the engine in the coolest conditions. Ant preferences anyone?...Joe

[D.A.Bagin]

I usually use mid-grade 89. I try to ride something else if it is over 75-80 degrees out

[Tom Lovejoy]

I run low grade regular for 13 years now in my Henderson, seem's good. Never could tell a difference if I payed more for premium, it runs fine with either/ about the same temps too I believe, good luck with yours.

[partshunt]

Thanks guys, Just askin, burnt a big hole in #4 piston, carb possibly went lean the last ten or twenty miles, No manifold leaks found. Its a 29 Four, troubleshooting cause is all..last fill up was 89 Octane, shoulda maybe stayed with regular fuel possibly.......Joe

[c.o.]

Joe!!! Sorry to hear about your '29. Here's hoping you have it back on the road soon. The weather is just getting good!!!

[partshunt]

Well Cory, you know what they say, "want some grief, buy a Chief, want more? Get a Four". She blew her guts on the freeway in four lanes of traffic, could not pull over and I think all those cars in the mirror wanted to run over me when the bike lost speed and slowed er down a bit on three cylinders. It blew out the dipstick due to combustion in the crankcase, raw fuel from number 4 cylinder lighting up downstairs below. About four explosions and lost about 1/2 my oil before I got er stopped. To think, it ran so sweet, no warning sign. The engine is apart on the bench and there is still oil dripping off the chasis. Its well splattered with oil. I have a piston coming in the mail and some other tid bits.....sucks, disapointing but ya gotta go on...Joe

[Robin--M]

Hi Joe,

Sorry to hear about your problem. I've been riding Indian fours for almost 40 years. Read your original manuals and do not set your carb too lean. That's the biggest problem that most people do on Indian fours. They will run good even when they are too lean and then you burn a whole in the piston. The 87 octane will work fine. Remember, back then those bikes were new, they didn't have high octane.

Robin Markey
Bob's Indian Sales & Service

[Tom Lovejoy]

Not a mechanic at all, but that's what I have always been told. Just like Bob said, they well run fine to lean and I have been told. When not pushed things and or problems don't show themself's, but push the speed up and hold it at all and the problems well show itself quickly. With the serious issues you showed, sure sorry to hear it though. Better to blow alittle black smoke than to lean. Just git it where you see alittle black smoke when hit the gas hard, but not back firing. That's what I have done with good results, best of luck.

[Tom Lovejoy]

Hey Joe, if I was you and had that experience - I would still be shaking, let alone would of wet myself :-) I have had my Henderson on the freeway here in L.A twice for only a couple miles, it ran like the wind and felt fine. But I thought if I did this very often, both my Deluxe and I would not live long. I stay off the freeway and just cruise along, it feels like it will last forever when running that way :-)

[partshunt]

Tom and Robin:- I surely heed your advise in all aspects. I had thought the settings on the carb were pretty close to what they should be, however, I will keep a keener eye on it for a richer mix next time out. . And like you say, a little black smoke would possibly saved my butt. I never was comfortable on the freeway with it. seems to be sceaming too hi a rev. Its running 18 and 40 tooth sprockets and 400 X 18 wheels. Sounds close to right to me but I dont know the RPM at 55 MPH. Can anyone calculate or estimate what the revs might be at 55 or 60 MPH?...Joe

[partshunt]

I have parts coming to repair this lame four but some I cant find so far. who makes the gaskets for the early fours in my year model 1929, it has the smaller exhaust manifold flange, (1.75" bolt space) and I need a set of 4 manifold gaskets for that. Also looking for pinion shims and the ball thrust large and small misc shims. need to reshim it a bit, reduce crank and bevel gear backlash. Any info on a source would help me a lot and be much apreciated...Thank you all in advance....Joe

[yhprum]

I'm not sure if high gear is 1:1 but I calculated my J model by measuring the tire circumference in feet then dividing that by feet per second at a given speed (that tells you the tire RPM) then dividing that by the final drive ratio if that makes sense.
MPH Feet Per Min
100 8800
90 7920
80 7040
70 6160
60 5280
50 4400
40 3520
30 2640
20 1760

[bikerdds]

Joe, I would also look for sources of ethanol free fuel. Unfortunately, California has few places. Look up ethanol free fuel on the net.

[tomfiii]

I have found several conversions to use for speed x rpm.

http://www.bakerdrivetrain.com/gearratios/rpmCalc.htm
http://performancetrends.com/tg.htm
http://www.bikerenews.com/Stories_Ar...Calculator.htm

[pisten-bully]

Joe, I would also look for sources of ethanol free fuel. Unfortunately, California has few places. Look up ethanol free fuel on the net.

Here's one:
http://pure-gas.org/index.jsp

I also wonder if marinas are a good place to find ethanol free gas, given how much trouble ethanol gives to boat engines.