Guide Chain Curiosity

[Eomund]

As many of you know, I'm swapping an L18 for an L20b. Ran into a bit of confusion with the chain guide. As I was trying to place the front cover on, the top left couldn't go flush. After playing around with it a bit and taking measurements, I found the mounting bracket for the chain guide was hitting. I compared it to the one on the L18 and this is what I found:

 

There's so much more material on the new one. Thankfully the old one is still in really good condition so I just swapped that one in, but I'm scratching my head as to why this one is different, different to the point of being unusable without having to possibly grind it down.

 

If anyone could shed some light on the subject, I'd appreciate it.

 

Ignore the backwards speaking for the title. That's what happens when you're typing and fake working at the same time...

[converted_to_datsun]

you know a L20 block is taller than an L18?.... Right?

[darrel]

The double hole, you probably used the wrong hole when bolting it in.

 

And yes. the l20b is taller.

[Eomund]

Ya and the l20b front cover was the one that didn't fit... The L18 one does. That's the obvious answer, but it's not the case in this situation. As far as the double hole, also not the problem.

[datzenmike]

 

Not seeing much difference between them. Where is it touching?

.

[Sealik]

The L20B and L18 guides are of the same....what brand is the lower one?

Notice the difference/distance between the mounting holes and the face/material of the guides...?.... 

 The top one was mounted correctly...always on the left bottom hole

Top of guide is pivoted over to take up any slack

[Eomund]

Not sure of the brand, came on the rebuilt motor. My guess is it was just manufactured with poor size standards.

[banzai510(hainz)]

who cares use the one that fits better

 

I have used new tensioners that will look the same but fit different.

One would be slight slck in the chain and the other would fit flush. Just dont know why.

 

 

most time if the front cover is off I would replace the slack side guide and the tensioner to keep it cheaper. Most times the chain and both sprockets and tight side guide are OK

[Eomund]

who cares use the one that fits better

That's what I'm doing. I was just curious if there was a reason why it was different. You know, aside from poor manufacturing standards.

 

And Mike, if you look at the non doubled hole, you'll see there's a lot more metal below the hole, that's hitting one of the front covers mounting holes.