Going to take a look at one, anything important I need to know?
I'm also curious what'd fit as far as upgrading the front fork and get a front disc? Possible, or a waste of time? Just enjoy as is?
Going to take a look at one, anything important I need to know?
I'm also curious what'd fit as far as upgrading the front fork and get a front disc? Possible, or a waste of time? Just enjoy as is?
LainfordExpress wrote: I'm also curious what'd fit as far as upgrading the front fork and get a front disc? Possible, or a waste of time? Just enjoy as is?
I'd say it's a waste of time...trying to engineer a replacement for the unique Honda front suspension and forks would be a ton of work, and they don't go fast enough to warrant the upgrades anyway.
S90 or CL90 front forks will fit them just fine. You'll need the complete headstock, forks, and a S90/CL90 hub, as they use a larger diameter axle. 14mm vs 12mm iirc.
I've fit S90 forks to a C100 for mylittle trials bike.
Buy I. Great piece of history. Racing versions made 20hp. You can upgrade forks with telescopic and disc brakes.
In reply to LainfordExpress:
Look for frame rot in the center of the Y. The brakes are already adequate, no real need to "upgrade" to disc. The front fork already works.
Fun vintage machine. Enjoy it for what it is, don't try to make it into what it isn't.
Well, it's bought. Gonna drive as is then decide whether to restore or not this winter.
Nice! Would you be open to sharing how much you paid for it?
LainfordExpress wrote: Well, it's bought. Gonna drive as is then decide whether to restore or not this winter.
I almost certainly overpaid, but it is all original down to the Honda toolkit. He was asking $1500, I paid $1200.
It ran great there and ran great for about half an hour tonight, then just died. Fooled with it some and it ran for about five minutes, then died and was really hard to restart. Disassembled and reassembled the throttle/brake assembly and it started right up and died again. I think something is out of whack with the throttle cable, either needs replaced or adjusted, neither are things I know how to do, but are also why I got it.
Hmm, reading up on chokes makes me think it might be the culprit. It started right up with the choke wide open, so maybe it needs adjusted? Would too closed of a choke make it stall?
Internets are also saying it could be a vacuum leak.
It started right up and ran for maybe 20-30 minutes. Then it just lost power, like it wasn't getting any gas, even when I twisted the throttle as far as it would go. Got it restarted and a few minutes later, it did the same thing.
I thought it might be the throttle cable because it was acting like it wasn't getting any fuel. After taking apart the throttle and putting it back together, it started right up and ran for maybe five minutes. Then just that over and over. If I tightened the throttle cable I could get it started with a lot of effort.
It could be the choke, I had the choke full open all night. It could be the throttle cable, maybe it's getting stuck and then I screw with it long enough it loosens back up. It could be a vacuum leak, but I don't really understand what that is and how to diagnose or fix that. Or it could be something more serious. :(
It was all the fun I ever imagined it could be while it was running though.
Now, I'm reading that the issue I'm having is pretty common for the ignition. Runs great until the electrics get warm then... I don't know what. Gonna take some fiddling.
Sound to me like the petcock it cloged or low flow so it runs out of fuel. let it sit and float bowl refills. that old magneto should be close to bullet proof except for the capasitir / condencer but that fail would pit the points fast.
44Dwarf wrote: Sound to me like the petcock it cloged or low flow so it runs out of fuel. let it sit and float bowl refills. that old magneto should be close to bullet proof except for the capasitir / condencer but that fail would pit the points fast.
The previous owner seemed competent and rebuilt the petcock, so I don't think it's that. I thought maybe fuel filter was clogged, but when I took the carbureator apart to check it out there was tons of gas in there. I'm guessing ignition, but don't know enough to figure that out.
I have learned don't rule out things that you think are ok Go ahead and check the petcock anyway. Do a nice toubleshooting list and work you way for simplest to most complicated.
Check the inter on testing spark. The engine in this think is same as the CT50, 90 etc. See the above link to the Yahoo CT group. There is lots of info there.
Checking the spark should be something like pulling the plug, attaching the ign. wire and making sure the plug is grounded. Then kicking the bike. Someone else may need to watch for the spark. Once you know you have spark you can rule that out
So... this may be a dumb question, but bear with me:
The petcock is just a valve between the fuel tank and the carburetor that either allows no fuel, the main fuel tank, or the reserve tank, right?
So, if I want to take it apart to inspect it, I'm going to have to drain the fuel tank first? Or find the line from the tank and reserve and clamp them so they don't leak.
Taking the carburetor off and apart led to a lot of spilled fuel even with the petcock set to "off". When my dad gets home I'll get him to help me check for spark.
Also, when I tore the carburetor apart, the float (I guess? Little metal cans attached together that rotated up and down, as if they would be floating on a pool of gasoline?) looked like it was either coroded, or had once been brass coated and the brass was coming off. I tried rubbing it with a cloth which at first was removing the coating/rust, but then no more would come off, which made me think it was just discolored brass coating.
I think on that engine -- but not sure -- the petcock is a valve as you describe, but it is part of the carb. the engine fuel is gravity feed, so the petcock allows fuel to flow when you want it to. When they go bad (rubber part decompose, or get clogged) they will let some fuel in. The engine will run until that limited fuel supply (stored in the float bowl) is used, then the engine will die.
The float is usually brazed when they are created (or plastic). It is normal to see brass. They do have the responsibility of metering the float bowl level. They let fuel in when the level drops to below the appropriate float bowl level. . Have a look for Mikuni spigot carb tuning. BUT, before you start taking apart complicated and delicate things like the carb. Check all the basics.
Start with: how old is the fuel? Is the fuel making it from the tank to the carb? Is the fuel making it into the engine Does it have spark?
Those questions and there answers should get you started. Remember to start small and simple then work your way to the more complex items.
LainfordExpress wrote: So... this may be a dumb question, but bear with me: The petcock is just a valve between the fuel tank and the carburetor that either allows no fuel, the main fuel tank, or the reserve tank, right? So, if I want to take it apart to inspect it, I'm going to have to drain the fuel tank first? Or find the line from the tank and reserve and clamp them so they don't leak. Taking the carburetor off and apart led to a lot of spilled fuel even with the petcock set to "off". When my dad gets home I'll get him to help me check for spark. Also, when I tore the carburetor apart, the float (I guess? Little metal cans attached together that rotated up and down, as if they would be floating on a pool of gasoline?) looked like it was either coroded, or had once been brass coated and the brass was coming off. I tried rubbing it with a cloth which at first was removing the coating/rust, but then no more would come off, which made me think it was just discolored brass coating.
Alright, so I'm pretty sure fuel is getting to the carb.
I pulled the spark plug and it is way dirty, completely black. I plugged it into its little electrical connector (so it wasn't in the engine) and tried to kick start it and couldn't see any spark. Do I just get a new spark plug, or should I check something else in the ignition system? And if so, how do I check it?
You could see spark? Or could not see any spark? Depending how old the plug is, consider getting a new one. But, for the sake of trouble shooting clean it with an old toothbrush and the electrode and strap with a bit of sandpaper (make sure you get the grit off before putting the plug back in the motor),If the plug is totally fouled, I don't know if you will see spark, but I think even a fouled plug would have a faint spark.no spark, then the next thing would be your points. Search the Yahoo group files for ignition issues.Hope this helps
Alright, so I cleaned up the old plug and still didn't get a spark. Two trips to Autozone later I had a shiny new NGK 4629 (First trip I left with a 4929) and now I have glorious beautiful sparks (and even managed to shock myself a little bit).
But alas, the bastard still won't start. I guess back to looking at the fuel system.
COOL! So if you have spark, you must not be getting fuel. Is there fuel in the floatbowl? Does it sputter and try to ignite?if there is fuel in the floatbowl, use carb starting spray and spray some in the carb opening and see if the bike will start.if it starts there is a carb problem. Could be as simple as a vaccum leak in between the carb and the engine
In years past you could clean plugs but over the past 8-10 years all MFG have stoped adding a glaze step to the insulator. With out the glazing step the insulator is left sort of porus and once flooded or fowled there all done. Why would they do this you ask? Cost / Time and fact 98% of the plugs now go in to fuel injected motors.
You need to check the petcock for open line flow remove the line from the carb place the line in a measureing jar and open the the petcock and see how much flows in to the jar in 10 seconds multiply by 6 to get flow per minute
So, I got it start and run again tonight, but it still dies when I cut the throttle. Also wrecked for the first time (trying to get going with too much throttle so it wouldn't die and wheelied it out from under me). If you try to let it ideal it just dies, and I can only get it start with the choke all the way open... So it has to be running too rich, right?
It's just weird that it seems to start and run pretty normal if I have it at part throttle.
I don't know how that carb's choke works. Does it restrict airflow to make the mixture richer? If so, could be a vaccum leak. Choke could be creating the vaccum needed to get the fuel from the carb. Get it running and spray carb starter spray around the place where the carb mounts to the intake and where the intake mounts to the engine. But before you do, get the engine warmed up.If the engine's idle changes when spraying, then that is where you vaccum leak is. Get a new gasket etc.
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