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Hello from Maryland!
- ajsfirehawk
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79 KZ650 SR
80 KZ1000 Z1 Classic
83 KZ1100 LTD
Z900RS
23 Mach 1
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- drakhen99
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The bike started right up. It sputtered a couple of times before running continually, and after 3-5 minutes of idling, reducing the choke to off, and then easily adding revs, the bike ran great again and I rode it around the neighborhood before more rain set in.
When I went to take the cover off, I noticed a small puddle underneath the bike, and after the "sniff test", I realized it's fuel. I have an appointment with my motorcycle mechanic for next week, so the bike will sit until Friday, when I'll make sure it runs (before borrowing a trailer, if needed) to get it to him. I expect he'll want to do a carb rebuild, sync, and replace some gaskets to stop the fuel leak.
Other than that, the bike is great, and I can't wait for it to be reliable
I also ordered a fuse box and blade fuses, so I'll either do that, or have my mechanic do it.
I'm easing into working on the mechanical bits. My experience is mainly car electronics, R/C cars, and doing a bobber conversion of my 05 VN800B.
-John
2019 Harley Street Glide Special (FLHXS)
2016 Vaquero - traded
2005 VN800B
1979 KZ650SR
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- 650ed
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drakhen99 wrote: ..... I have an appointment with my motorcycle mechanic for next week..... I expect he'll want to do a carb rebuild......
You need to think twice about having anyone rebuild your bike's Mikuni VM24SS carbs. Replacing gaskets or even some rubber pieces is one thing, but replacing jets, jet needles, float valves, etc., in other words any METAL pieces is a whole different issue. Unless someone has gone in there and damaged the metal pieces they should not be replaced. The original Mikuni parts are VERY precise, but many of the new aftermarket parts are not. If the mechanic is going to fiddle with the carbs tell him NOT to mix parts between carbs. If the carbs are leaking through the overflows read the blurb below. If they are still leaking after the engine has been shut off for a while you also have a petcock problem because the 1979 KZ650 vacuum operated petcock should stop the flow of fuel when the engine is turned off.
Fuel coming out of the overflow hose is the common symptom of the 3 possible problems described below. Remember - NO SMOKING or other activities that could ignite the fuel while working on carbs!
The float valve is not sealing. This may be (and probably is) just a matter of some minor dirt in the float valve and is very simple to remedy and can be done with the carbs still on the bike. Turn off fuel; drain carb by loosening big brass screw near bottom; and remove the 4 little screws on the bottom of the carb bowl. This will enable you to remove the carb bowl. You will then see the float. If you carefully remove the float you will see a stubby little needle that mates with a brass orifice; together, these two pieces are the float valve. Assuming there is no obvious damage to the needle or seat, use a Q-tip and some carb cleaner to clean the seat of the orifice and the needle. Be careful not to bend the tang that is attached to the float. This tang is the piece that the bottom of the float valve needle rests upon, and it determines the fuel level in the bowl, so bending it will change the fuel level. With the float valve cleaned it should no longer leak. To prevent a re-occurrence a quality inline fuel filter should be installed between the fuel tank and carbs. If there was damage the needle and seat should be replaced as a set; they are available.
The brass overflow tube inside the carb bowl is damaged. When you remove the carb bowl you will see a brass tube attached inside and rising toward the top of the bowl. This is the overflow tube and it leads directly to the overflow nipple on the bottom of the carb. Normally, the fuel level within the bowl rises somewhat close to the top of this tube. If the tube becomes cracked or separates from the bottom of the carb bowl fuel will flow through it and out through the overflow hose. Checking the condition of the tube is very easy after you have removed the carb bowl from the carb. Simply hold the bowl level and fill it up near the top of the tube with water or alcohol and see if it leaks. A slight crack in the brass overflow tube can be difficult to find. You can connect a rubber tube to the overflow nipple, fill the bowl with water, put finger over the open end of the brass overflow tube and blow in the rubber end and look for bubbles. If it does the best remedy is to replace it although some folks have found creative ways to repair them.
The fuel level is set too high. This condition occurs when someone has bent the float tang as mentioned above. This condition can be checked using what is referred to as the "clear tube test." The test involves attaching one end of a clear piece of flexible tubing to the carb drain hole and holding the other end of the tube above the bowl/carb joint. When the fuel is turned on it should rise in the tube to a level 2.5 - 4.5 mm below the bowl/carb joint. If the fuel rises higher than that level it may run into the cylinders or over the upper end of the brass overflow inside the carb bowl (mentioned above) in which case it will run out the overflow hose. This condition is corrected by removing the float and gently bending the tang to raise the float valve needle position. Doing this may take several tries before achieving the desired fuel level.
Correcting each of these three conditions involves removing the carb bowl. This task can be made easier if a short screwdriver bit is used, and depending on which carb you are fixing a mirror may help you locate the screws on the bottom of the carb bowl. Also, it is not a bad idea to have a new carb bowl gasket available in case the old gasket is damaged while removing the carb bowl. Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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- drakhen99
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Rode it for 10 or so miles, we'll see what she does later in the day.
-John
2019 Harley Street Glide Special (FLHXS)
2016 Vaquero - traded
2005 VN800B
1979 KZ650SR
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- drakhen99
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-John
2019 Harley Street Glide Special (FLHXS)
2016 Vaquero - traded
2005 VN800B
1979 KZ650SR
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- drakhen99
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The bike ran fine last week, and then when I got to a stop sign near my house on Saturday morning, I stalled it - oops. Fuse blew (again), and I pushed it back home. Replacing the fuses again did nothing, but cleaning the battery cable ends did. Started her back up and got her to the mechanic. Here's what he's done:
1. Tune-up (idle speed, carb adjustment screws (there were 2 turns out, he put them at about 1.25 turns out)
2. Replaced stock fuse box with one I ordered off Amazon (which uses blade fuses)
3. Replaced headlight with H4 kit
4. Replaced rear brake light switch (turns out THIS is what was causing the main fuse to blow)
5. Oil + filter change (found out the bike was missing the filter seat and drain plug washer)
6. Replaced front fork seals and replaced stock fork springs with Progressive springs
7. Cleaned the front brake master cylinder. It was creating a pressure buildup, which led to no slack at the lever
8. General check-over.
So far, he says the bike warms up better, shouldn't have the hanging revs like before, the engine is strong, and there's still a slight fuel issue, where the #1 cylinder has a little bit of gas in the drain tube. He thinks it's a sticking float or needle (I don't have the email right in front of me), but we'll address that after I ride her some more.
Other than that, the charging system is OK, the points/condenser were replaced recently, and the bike is in good shape.
Glad to know I didn't get a basketcase, and it isn't gonna cost me an arm and a leg to "baseline" the bike
-John
2019 Harley Street Glide Special (FLHXS)
2016 Vaquero - traded
2005 VN800B
1979 KZ650SR
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- drakhen99
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I got the bike back Saturday, and she runs better than ever! Only got a short ride in (heavy rains were incoming), but so far so good. Made a couple of stops, and no blown fuses
There's a slight hiccup when taking off from a stop where it acts like there's a stumble between the idle jet and main jet, so you have to ease onto the throttle to take off. Not a big deal.
Overall, quite happy with the bike, and I'm hoping I get a chance to put a few more miles on her soon!
-John
2019 Harley Street Glide Special (FLHXS)
2016 Vaquero - traded
2005 VN800B
1979 KZ650SR
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- drakhen99
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Bike ran great, but it was funny - the "stop lamp" light on my dash wasn't lighting up, until about halfway through my ride. Weird, huh?
-John
2019 Harley Street Glide Special (FLHXS)
2016 Vaquero - traded
2005 VN800B
1979 KZ650SR
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- 650ed
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1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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- drakhen99
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.I rode the bike at lunch time, and the lamp on the dash worked just fine. I'll be going out in an hour or so to show a co-worker, at which point I'll have him see if the stop lamp is illuminating, and tomorrow morning, I'll have my wife see (as the bike will definitely be cold by then).
Thanks,
-John
2019 Harley Street Glide Special (FLHXS)
2016 Vaquero - traded
2005 VN800B
1979 KZ650SR
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- drakhen99
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While I'm at it, is there a preferred brand of engine guards and highway pegs? I've got knee problems, and the bent-knee position on this bike causes pain after 20-30 minutes of riding. Would love to be able to stretch out like on my cruisers.
Thanks,
-John
2019 Harley Street Glide Special (FLHXS)
2016 Vaquero - traded
2005 VN800B
1979 KZ650SR
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- 650ed
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www.kzrider.com/modules/ServiceManuals/K...Owner's%20Manual.pdf
Ed
1977 KZ650-C1 Original Owner - Stock (with additional invisible FIAMM horn)
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