Question:. My friend has an 86 LXE and when you squeeze his front brakes the
brake handle touches the handlebar, with no pressure build-up in the line.
Now this is what he had done to the bike: Rebuilt the calipers, installed
new brake lines and put in a new master cylinder. However, he still has the
problem. Close to a quart of brake fluid has been used to bleed the lines.
I told him that I would take his problem to the think tank and see what everyone can come up with. So there you have it.
Answer: This problem is easy to fix although somewhat tricky. Air gets trapped in the end of the master cylinder, because the cylinder is pointing up when the handlebars are in their normal position. Turn the handlebars all the way to the left so that the master cylinder is at least level. Cover the top of the bike with an old blanket in case brake fluid spills. Get a clean pump oil can and I do mean clean (NO OIL!!!!!). Fill the oil can with DOT4 brake fluid, attach a short hose to the oil can nozzle. Open one caliper bleeder at a time. Attach the hose and pump brake fluid backward through the system. (Don't let the oil can go empty or you will force more air into the system.) You may have to remove fluid from the master cylinder as it fills up. You can watch the air come out of the system as this is done. DO NOT pump the master cylinder lever while doing this. I've done this with many motorcycles over the years and it works every time. It also works for the clutch cylinders.
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Question: Once I finally get my clutch fluid cover off, how do I drain the fluid to change it? Is there a valve? Do I just add new fluid?
Answer: Yes, use Dot 4 brake fluid for both brakes and clutch. The bleed screw is under the cover with the gear shift directions on the left of the bike ( 1 N 2 3 4 5 ). The screws remove with an 8mm socket. Then, when you remove that cover; there is a tube on the left around the middle of the area where you are looking. It is also an 8mm. You can bleed that the same way you bleed the brakes.