Harley x-90
- Thread starter RLE
- Start date
I have 1975 Harley X90 that I'm starting to work on. I plan on bypassing the oil injection pump and pre-mixing the fuel. What oil is used in the gear box? I have two-cycle oil for mixing with the fuel but can't find any definitive info on gear oil. Also, can't find pre-mix ratio. Is it 50-1 or 32-1 or ...?
Thanks in advance!
R
Thanks in advance!
R
@x-90 rider will be able to tell you, when he's back online.
He's our resident x-90 guru !
Excuse me, I didn't realize we hijacked this thread, until after I posted.
He's our resident x-90 guru !
Excuse me, I didn't realize we hijacked this thread, until after I posted.
Hey guys!
Thanks for the input! It's nice to be part of a community that's so knowledgeable and so willing to share!
I did error on the side of caution and mixed up a 32-1 ratio but I couldn't get the engine to run. It wouldn't even pop-off. The plug was fouled (fuel and oil) everytime I removed it to check. I ultrasonic cleaned the carb and put in a new needle. I actually removed the carb from the intake and will try to start again after the engine airs out. I get a "spark" (not sure what a good spark looks like) when I rest the plug on the engine and turn it over, but can't say if it still sparks in the combustion chamber. The spark plug is an old Champion 'resistor' plug and the next step will be to replace with a non-resistor plug and give her a go again. I checked the rear brake bulb with an ohm meter and both filaments are fine. I checked the points (without removing the magneto rotor because I don't have the proper puller) and sprayed with electrical cleaner and wiped 'em clean.
I'll keep you posted!
Thanks for the input! It's nice to be part of a community that's so knowledgeable and so willing to share!
I did error on the side of caution and mixed up a 32-1 ratio but I couldn't get the engine to run. It wouldn't even pop-off. The plug was fouled (fuel and oil) everytime I removed it to check. I ultrasonic cleaned the carb and put in a new needle. I actually removed the carb from the intake and will try to start again after the engine airs out. I get a "spark" (not sure what a good spark looks like) when I rest the plug on the engine and turn it over, but can't say if it still sparks in the combustion chamber. The spark plug is an old Champion 'resistor' plug and the next step will be to replace with a non-resistor plug and give her a go again. I checked the rear brake bulb with an ohm meter and both filaments are fine. I checked the points (without removing the magneto rotor because I don't have the proper puller) and sprayed with electrical cleaner and wiped 'em clean.
I'll keep you posted!
Hey guys!
No joy! Still can't get the engine to pop over. Reinstalled the carb on the intake, removed the coil, cut a bit off the end of the spark plug lead that attaches to it, remounted it, and get spark when the plug is sitting on the engine and I kick it over by hand. Still waiting for a new non-resistor plug to arrive in the mail. I "seem" to have good compression but get a lot of fuel mist and vapor backing-up through the carb when kicked over. I understand that these 2 stroke engines DON'T have reed valves but only bypass ports. I also understand that because of this these engines run quite rich at idle. Am I missing something here?? Ugh.
No joy! Still can't get the engine to pop over. Reinstalled the carb on the intake, removed the coil, cut a bit off the end of the spark plug lead that attaches to it, remounted it, and get spark when the plug is sitting on the engine and I kick it over by hand. Still waiting for a new non-resistor plug to arrive in the mail. I "seem" to have good compression but get a lot of fuel mist and vapor backing-up through the carb when kicked over. I understand that these 2 stroke engines DON'T have reed valves but only bypass ports. I also understand that because of this these engines run quite rich at idle. Am I missing something here?? Ugh.
You might have to have a handful of NEW plugs to get it to start up. Buy some cheap ones anything close to the correct heat range and thread length and see what happens. 2strokes are bad about permanently gas fouling a plug. Read up on that if you have a moment. So if it doesnt start on about the 5 or 6 kick dont continue trying until you remove the plug and vent the cylinder then reinstall and repeat. Once you get it started and cleared out then install the proper plug would be my next move after checking you points and other variables as has been mentioned by x-90 rider.
Thanks guys! Interesting. I did some research online and the quote that stands out most is "compared to 4 strokes, 2 strokes are plug eating machines."
I had this motorcycle when I was 12 years old. Had a lot of fun with it. It got sold to a neighbor after I moved out of the house but I re-acquired it a few decades later. It didn't have a speedometer on it when I had it initially, but it did have a rear brake light lens. Fast forward a few decades and I received it back WITH a speedometer but a bent brake light housing and no red lens. I suspect they were doing wheelies and lost control.
So...it IS possible to get a weak spark if the wiring to the brake light isn't a complete circuit and the spark I see isn't sufficient for combustion?
I don't have the proper tool to remove the rotor. Someone posted NOT to attempt to remove without the proper tool because the crankshaft end can get damaged beyond repair. Can I carefully use a standard puller?
I had this motorcycle when I was 12 years old. Had a lot of fun with it. It got sold to a neighbor after I moved out of the house but I re-acquired it a few decades later. It didn't have a speedometer on it when I had it initially, but it did have a rear brake light lens. Fast forward a few decades and I received it back WITH a speedometer but a bent brake light housing and no red lens. I suspect they were doing wheelies and lost control.
So...it IS possible to get a weak spark if the wiring to the brake light isn't a complete circuit and the spark I see isn't sufficient for combustion?
I don't have the proper tool to remove the rotor. Someone posted NOT to attempt to remove without the proper tool because the crankshaft end can get damaged beyond repair. Can I carefully use a standard puller?
Take the plug out. Turn off the fuel. use a drill and a socket to spin the engine for a coup[le of minutes. It sound like you have a crankcase full of fuel. This will "unflood" it. Try again with a new plug after the fuel smell goes away. I hope that makes sense.
FWIW: I have a bunch of 2 stroke small equipment. Saws, post hole diggers, stuff like that. All air cooled. I use AMSOIL Sabre oil in all of them. I mix up a can at 50:1 and I just use that gas in everything. Amsoil claims it is safe for ANY air cooled engine at 100:1. I have used at 100:1 and it seemed to work great, but I just feel better at 50:1. The stuff comes in little packets for one gallon. I can't remember the last time I fouled a plug. I change my plugs when I change blades on equipment just because I think I should. Good Luck!
FWIW: I have a bunch of 2 stroke small equipment. Saws, post hole diggers, stuff like that. All air cooled. I use AMSOIL Sabre oil in all of them. I mix up a can at 50:1 and I just use that gas in everything. Amsoil claims it is safe for ANY air cooled engine at 100:1. I have used at 100:1 and it seemed to work great, but I just feel better at 50:1. The stuff comes in little packets for one gallon. I can't remember the last time I fouled a plug. I change my plugs when I change blades on equipment just because I think I should. Good Luck!
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Greetings All!
Thanks to all the helpful suggestions and a special shoutout to sparkwizard! I tried the socket with a drill on the rotor nut for a few minutes and then let it sit overnight. I kicked it a few times and no joy. I sprayed a quick toot of starting fluid in the carburetor intake and she fired right up! Smoked a bit (ok...a lot) but idled nice. Let it run for a few minutes and tried to start her again 20 minutes later and she fired up on one kick!
I blew a filament in the rear brake light and when the rear brake is pressed, the engine would want to die. Been online looking for 6v, 18w/5w bulbs. They're there, but expensive. Has anyone put LED bulbs in? I found some 6v with the proper brass offset connector and approximate wattages. Will they work in the magneto system or will their smaller current draw cause problems in the charging system?
WhooHoo!! 48 years later and it sounds the same and smells the same!! Trip down memory lane no doubt!!
I know it had a brother, a Z90 that was a slightly larger frame and made for the street. Has anyone been able to get their X90 registered and licensed for street riding in their state? Obviously it would just be tooling around for kicks and grins once-in-a-while.
Thanks to all the helpful suggestions and a special shoutout to sparkwizard! I tried the socket with a drill on the rotor nut for a few minutes and then let it sit overnight. I kicked it a few times and no joy. I sprayed a quick toot of starting fluid in the carburetor intake and she fired right up! Smoked a bit (ok...a lot) but idled nice. Let it run for a few minutes and tried to start her again 20 minutes later and she fired up on one kick!
I blew a filament in the rear brake light and when the rear brake is pressed, the engine would want to die. Been online looking for 6v, 18w/5w bulbs. They're there, but expensive. Has anyone put LED bulbs in? I found some 6v with the proper brass offset connector and approximate wattages. Will they work in the magneto system or will their smaller current draw cause problems in the charging system?
WhooHoo!! 48 years later and it sounds the same and smells the same!! Trip down memory lane no doubt!!
I know it had a brother, a Z90 that was a slightly larger frame and made for the street. Has anyone been able to get their X90 registered and licensed for street riding in their state? Obviously it would just be tooling around for kicks and grins once-in-a-while.