Differences between G and L frames

[BigD_83]

I have not had the chance to be able to put a G frame and an L frame up side by side and compare the differences, but I was wondering if anyone can point me in right direction or had some insights.

Does anyone know of a website that shows frame geometry?

The reason I'm looking is that I am trying to wrap my head around some exhaust pipe fitting issues. I recently picked up a set of used pipes that I thought had come off a G, but just do not fit well on my 650GD. These are aftermarket, and came with an assortment of hangers and bolts, and I'm starting to think they actually came off an L

The pipes are 4 into 2 with no H-pipe. I'm okay with that. What bugs me is that I cannot get the right side to mount on the existing bracket without putting a tremendous amount of torque on the header, which then causes it to not seal properly at the head. I don't think it would be too much of an issue if I had both header bolts available to secure the pipe, but at the moment I only have one bolt/header. That should be rectified this winter.

In the meantime, I'm trying to understand how the frames match up geometry-wise so I can think about the best way to modify these pipes. I can use the hangers that came with them, but the right hand pipes end up 1) touching the oil pan, and 2) hanging much too low at the mounting bracket for my liking; functional, but ugly.

For whatever reason, the left hand set hangs fine on the existing frame bracket without using the extra hangers.

On the plus side, the mufflers are clamp-on, NOT welded like the stock pipes so I have room to put a joiner in.

Was the radius of curvature on the header pipes different between the G and L exhaust?

I have a set of black 550M header pipes with no mufflers that came on the bike, and fit well enough (or maybe not...perhaps the reason for the broken header bolts?) and I'm thinking I might get someone to help me cut them and fabricate a connection to the aftermarket mufflers instead of modifying these other pipes

[DanTheMan]

I have not had the chance to be able to put a G frame and an L frame up side by side and compare the differences, but I was wondering if anyone can point me in right direction or had some insights.

Does anyone know of a website that shows frame geometry?

The reason I'm looking is that I am trying to wrap my head around some exhaust pipe fitting issues. I recently picked up a set of used pipes that I thought had come off a G, but just do not fit well on my 650GD. These are aftermarket, and came with an assortment of hangers and bolts, and I'm starting to think they actually came off an L

The pipes are 4 into 2 with no H-pipe. I'm okay with that. What bugs me is that I cannot get the right side to mount on the existing bracket without putting a tremendous amount of torque on the header, which then causes it to not seal properly at the head. I don't think it would be too much of an issue if I had both header bolts available to secure the pipe, but at the moment I only have one bolt/header. That should be rectified this winter.

In the meantime, I'm trying to understand how the frames match up geometry-wise so I can think about the best way to modify these pipes. I can use the hangers that came with them, but the right hand pipes end up 1) touching the oil pan, and 2) hanging much too low at the mounting bracket for my liking; functional, but ugly.

For whatever reason, the left hand set hangs fine on the existing frame bracket without using the extra hangers.

On the plus side, the mufflers are clamp-on, NOT welded like the stock pipes so I have room to put a joiner in.

Was the radius of curvature on the header pipes different between the G and L exhaust?

I have a set of black 550M header pipes with no mufflers that came on the bike, and fit well enough (or maybe not...perhaps the reason for the broken header bolts?) and I'm thinking I might get someone to help me cut them and fabricate a connection to the aftermarket mufflers instead of modifying these other pipes

I have G pipes on my L bike, and BassCliff has L pipes on his G.

Was the radius of curvature on the header pipes different between the G and L exhaust?
I've found no difference in radius curvature, the G pipes had a little tighter fit at the mounting point on the frame, but i didn't have to do any fabricating to fit up G pipes to my L. There might be some differences between earlier models vs later models though, I don't know.

[BassCliff]

Hi,

Dan is talking about our GS850's.

Hey Dan, maybe the next time you're in town we could swap our exhausts?


Thank you for your indulgence,

BassCliff

[jaywelchy]

Me too.....need to know.

For my example:

Is the gs1000s frame the same as a gs1000L?? Lets say both are same year frames.......if there ARE differences I need to change an order! :-(

[DanTheMan]

Hi,

Dan is talking about our GS850's.

Hey Dan, maybe the next time you're in town we could swap our exhausts?


Thank you for your indulgence,

BassCliff

Hmmmm......I think the next time I'm in your town on a bike, it'll be my 1100G. No, I'm NOT trading those pipes for yours! Sorry, it seems that your 850G just has to sound like an 850L!

[tom203]

I would think that the pipes would be identical, though maybe the mufflers might be different. The system on my "L" model is most likely the original and is stamped "GS 650 GL" with an "X" to indicate 1981 model year. The hangers seem to support the system without any distortion and it's even both sides. Maybe one of your pipes is from another model. I would guess the frames are the same, with the L having different forks, midget gastank, and lowered seat to please short people like me!

[Steve]

... I recently picked up a set of used pipes that I thought had come off a G, but just do not fit well on my 650GD. ... The pipes are 4 into 2 with no H-pipe. ...

As far as I know, the only "G" pipes that did not have an H-pipe were the '79 850s.

Starting in '80, I think all the four-cylinder bikes had H-pipes of one form or another.

You might not have "G" pipes.

.

[BigD_83]

Hi Steve. Thanks for your input.

Buried somewhere in the verbose original thread I think I noted they are an aftermarket pipe, but came off an "L". Apparently I didn't ask the right questions when I bought them.

I've been told there is a glut of old GSes and clones/knockoff parts for GSes in China; I don't recall the manufacturer off hand (Hua Tong? Lu Tong?). They sound nice to me (re: not LOUD), but lack a little midtone that may be a result of having no common collector

Still, apart from hanging funny, the metal looks decent, and hands-down beats the old mufflers that I couldn't tear off the bike fast enough (and had no silencers in them).

I recall seeing a recent thread by 7981GS or Flaming Chainsaws [maybe (?)] where they applied the use of a ratchet strap to make the pipes conform. That might end up being the least expensive and easiest option until I can get those old header bolts out and retapped.