Timing chain tension = non running FT500 on bike for sale?

[johnnymot1]

I'm going to be methodical and double check my valve clearances, put a scope in the cylinder and a few other things before pronouncing the motor needed to swap.

My "ear" is evolving to hear a sound like a playing card in a fan blade too...Sort of like the timing chain......... If they are running good, I have no interest. It's these puzzles that keep me obsessed.

[J6G1Z]

Have you heard of the old stethoscope trick?

You take a long screwdriver, ratchet extension, steel rod, etc, or you could use a length of flexible tubing/hose. Then hold one end to your ear & use the other end to probe around the engine while it is making the noise. This will help you locate the area that the noise is coming from.

Good luck
J.

[johnnymot1]

I ended up just ordering a cheap engine stethoscope to avoid the acrobatics I needed to keep the engine running via the throttle and listening. Since I live in a remote area, I can't run out and pick up a special tool/part etc, so I've learned to be patient. Luckily I have several other FT500 projects, a CB100 project for my wife and a few more which means no down time or waiting when one or the other project requires a special service tool I overlooked or a specific tool I don't have, but need.

Speaking of which I'm going to purchase a motorcycle borescope, because I need it for this, and it will have use on other projects. Does anyone have a favorite or best brand of socpes they've owned or used. Sort of looking for a middle of the road price range. I've ordered two motorcycle specific feeler gauges and two each universal feelers to adjust both the intake and exhaust valves with feelers underneath simutameously to ensure accuracy too.

I'm going to make sure I've exhausted every possible "external" adjustment, investigation etc, then some internal by borescoping the cylinder before I decide to swap this engine out for another. Even if it comes to that, I'll still be obsessed until I find out the source of the noise.

[scottly]

When you first mentioned the original spark plug had no gap, I wondered if there might be something bouncing around inside the combustion chamber...
I picked up this USB borescope for less than $20 including shipping. It's less than 8mm in diameter. I took a pic of an XR500 piston just to try it out. 

[johnnymot1]

Very cool Scottly, and thanks. I ended up ordering one that is almost identical with a 5.5mm diameter camera, and about the same price. I have an unused laptop that will work perfect with it in the shop.

I hadn't thought about an object in the cylinder being the cause of the no gap on the plug, but it makes sense. Given the overall treatment of the bike, I think it's entirely possible something was dropped in there. I did get my two .004 motorcycle feeler gauges in yesterday and checked the exhaust valve clearance with both under each rocker simultaneously. All was good and those little motorcycle specific feelers are perfect for the job...The old "right tool for the job" adage, very true.

Once my other tools come in (remote area means order, be patient, and wait a week and/or plan ahead to know what you need), I'm going to double check my intake valve adjustment with two feelers at the same time, scope the engine and head and use my nifty stethoscope to get a better idea of the origin of my "noise", before dropping that engine and putting in the other sitting beside it. If I do, I would go into that engine and end up doing a bit of a high performance build on it for my ascot/hurricane hybrid cafe project.

I'm hoping at some point I can "reverse" the tank coating job inside the tank too. It's a pretty nice tank, cosmetically, but he coating job was botched!