Thickness of tonti frame under seat

[Adv_hoon]

I have just bought a 1977 850 T3 California that I parked in my parents garage. I took a lot of measurements as I wanted to order some parts for modification. But one thing I forgot to measure was the diameter of the two frame tubes running horizontally under the seat. Can anyone help me with this? I can find drawings of all geometry and measurements between mounting holes etc. but no description of the actual thickness of the tubes?

[Ralph Plant]

I'm looking at 30.15mm on my 78 LeMans

[Adv_hoon]

I'm looking at 30.15mm on my 78 LeMans

Thank you so much!

[Turin]

What are you doing to the frame?

[moto]

I'm looking at 30.15mm on my 78 LeMans

About the same for my standard T3. Say 30mm w/o paint.

[Adv_hoon]

What are you doing to the frame?

I am trying to avoid to do anything, actually. I have been playing around with different ideas for a solo seat. The one from harpers and the original police seat are a little bit too "chunky" to my eyes. I actually really like this one, but I think it must be either custom made or from another motorcycle as it sits lower than either harpers or the police one:




So my reason for asking for the diameter was in order to make mounts for a "bobber-like" seat. And as I do not want to modify the seat and want to be able to put it back to original, then instead of welding on mounts I thought about making clamps that hold on to the frame rails, just as clamps used to hold the handlebars.

[Dukedesmo]

Just for confirmation, '79 built LM2 - 30mm as above.

[Mayor_of_BBQ]

I am trying to avoid to do anything, actually. I have been playing around with different ideas for a solo seat. The one from harpers and the original police seat are a little bit too "chunky" to my eyes. I actually really like this one, but I think it must be either custom made or from another motorcycle as it sits lower than either harpers or the police one:




So my reason for asking for the diameter was in order to make mounts for a "bobber-like" seat. And as I do not want to modify the seat and want to be able to put it back to original, then instead of welding on mounts I thought about making clamps that hold on to the frame rails, just as clamps used to hold the handlebars.

trusted member named Mike Tibereo was always here raving about a harley solo seat repro from ebay. I cannot direct you to the exact one, but maybe a good starting point in your search?

[Adv_hoon]

trusted member named Mike Tibereo was always here raving about a harley solo seat repro from ebay. I cannot direct you to the exact one, but maybe a good starting point in your search?

Oh thank you very much! Would really love to know what exact model it came from. Perhaps I should try my luck in a Harley forum and see if someone can spot it from just that picture.

[moto]

Mike is still active here. Try sending a PM to mtiberio.

[Turin]

Here is my old T-3 that I did back in the '90s. All I did was take a Tonti solo seat and carve it into shape with an electric carving knife to get the shape I wanted. Then I had it upholstered to taste. It's a lot easier than frame mods.




(tasslles and fishtails are a bit embarrassing decades later.)

[Adv_hoon]

Here is my old T-3 that I did back in the '90s. All I did was take a Tonti solo seat and carve it into shape with an electric carving knife to get the shape I wanted. Then I had it upholstered to taste. It's a lot easier than frame mods.




(tasslles and fishtails are a bit embarrassing decades later.)

I thought about going that route and just modifying a solo seat until it looked like I wanted. But now I ended up buying a cheap seat for a sportster that I will tryto see if I can make work.

If it looks embarrassing then you just have to wait a few more years, then it will probably be hip again :)

Mike is still active here. Try sending a PM to mtiberio.

Thanks a lot. I actually ended up buying a cheap sportster seat from ebay which I liked the look of and based off my measurements might work as intended. Time will tell :)

[Mayor_of_BBQ]

Mike is still active here. Try sending a PM to mtiberio.

is he? I hope so. Have not seen him post since he sold "the world's fastest eldovert" and said he was facing grave health issues

[moto]

He posted on April 9, 2022.