Motor number. Help please

[karatekid]

Just learning here and I just pulled the motor because the front cam chain guide is all in my filter and I noticed my motor numbers are 447-113051 so what year is this motor?. My title and frame say 1981 but unsure of the motor as I've tried to decipher the numbers on here but I'm a little goofed up today I guess can somebody tell me what I need to know please?

 

[650Skull]

75 XSB, Numbers start from 100101.

81 engines had factory electronic ignition, (1980-1984), so there were no points or advance rod and weights under the cam covers. You may find your engine still has them although they wouldn't have been used unless the factory electronic ignition has been removed.

Basically it is the same engine from 74-84

 

[XSLeo]

On the frame neck is a number, not the number on the white sticker. They came from the factory with matching numbers. You use the same ID number to year chart to determine the engine year the same way you do the frame.
I agree with 650Skull on the year of your engine.
Nothing to worry about. Some people just swap engines, rather than fix what they have.
All the engines were basically the same from 74 up. They changed the cam chain adjuster a few times, the engine breather and carbs. Putting a pre 80 engine into an 80 up TCI bike was easy just use the 80 stator and rotor. You can even take out the points stuff in the head.
Leo

 

[karatekid]

Thanks Leo and skull I'm just gonna go with the year you stated its not a big deal to me I just wanted to know for sure so thanks. I've got all the new electronics on it pma and pamco with kick only and the bike runs like a champ I just pulled the oil filter from the side and noticed all the black plastic caked in there and decided to put a new front slider on. This motor surprised me that it ran so good even tho all that junk was in there. Any more info on parts I should buy would be great, all I have on my list is the front slider and maybe a cam chain but I'm not sure i want to even buy the cam chain since it runs so good and with the new tensioner spring I just got it looks like I have plenty of room but I'm no expert yet.

 

[XSLeo]

Pull the sump filter too. It's on the bottom of the engine. Attached to the inside of the sump plate. It will catch the big stuff that falls off the front cam chain guide.
The e-starter gears have a rubber o-ring on one gear, this help cushion and quiet the gear engagement as it slides over. This co-ring breaks down. It is 40 some years old. This may be the stuff you are finding on the right side oil filter.
The black plastic on the front guide is hard unlike the o-ring bits that are softer.
If it runs ok and you don't have excessive noise from the chain running on the guide then I might run it awhile and watch what you find in the oil and both filters.
If and when you tear it down for the guide. you can inspect everything else. You may find that all you need is the guide and chain. You may find it needs new rings and maybe piston.
Hard to say till it's apart.
Leo

 

[XSLeo]

Pull the sump filter too. It's on the bottom of the engine. Attached to the inside of the sump plate. It will catch the big stuff that falls off the front cam chain guide.
The e-starter gears have a rubber o-ring on one gear, this help cushion and quiet the gear engagement as it slides over. This co-ring breaks down. It is 40 some years old. This may be the stuff you are finding on the right side oil filter.
The black plastic on the front guide is hard unlike the o-ring bits that are softer.
If it runs ok and you don't have excessive noise from the chain running on the guide then I might run it awhile and watch what you find in the oil and both filters.
If and when you tear it down for the guide. you can inspect everything else. You may find that all you need is the guide and chain. You may find it needs new rings and maybe piston.
Hard to say till it's apart.
Leo

 

[karatekid]

Xsleo where is that gear located i have the top end off and the cam chain sliders are practically fine and all that black plastic on the side over filter is quite a bit off plastic

 

[5twins]

The e-start gear Leo is referring to is called the #4 starter gear. It is located under the right side engine cover, under the clutch .....

Obviously, the clutch assembly needs to come off to access it. Here's a shot with that done .....

The #4 gear is the inner one in the stack, below the top gear you see in the photo above. The o-ring Leo refers to is more like a thick rubber washer bonded to the inner face of the gear. You can see it in this parts diagram. It's the raised portion around the hole in the center of the gear .....

If the bike is new to you, the accumulation you've found on that filter may be a long time build-up that occurred because the P.O. didn't clean that filter often enough.

 

[karatekid]

Looks like there's alor more black plastic located down here where here in this hole left of the starter gear

 

[karatekid]

So is the only plastic components in this engine the cam chain sliders and the gear behind the clutch

 

[XSLeo]

The cam chain guide is a black plastic part glued to an aluminum backer.
The ring on the starter gear is hard rubber.
Those are the two most probable sources of black stuff in the filters. The rubber ring on the starter gear is most often found in as ground up form. The front guide in long strips, these come from the edges of the guide.
Leo