Frame loop & seat inspiration

[Vigo The Carpathian]

Hi all, I'm new here, about to lay into a 1980 XS400 special. Was hoping to get an idea of how my seat plans might pan out from those of you who have done something similar.

I'm looking to do an upturned frame loop similar to the setups on these CB's:

The clean frame line along with the low seat profile appeals to what I'm looking for visually.

However, while the CB frame tubing seem to continue a set width apart through most of the seat and both sides are a bit closer together, I've noticed the XS400 frame is a little wider and seems to widen more still around the rear suspension mounts.

Has anyone here gone with a similar style seat and if so, is the difference in frame negligible? I would love to see some in progress pictures as well as what you all have done in the way of a seat pan.

Thanks in advance for the help. I'm sure I'll be doing a lot of lurking on here in the upcoming months.


PS- If anyone has any decent info about modifying the tank mounts to fit an early XS750 tank, that'd also be lovely.

 

[J-Rod10]

I've seen a lot of people make that style seat out of a skateboard. I don't know the width of one, compared to your frame, but it seems to be a popular base for the brat seats.

 

[bcware]

Love that last photo in black and white. It says dunlop on those sidewalls but they are clearly Kenda Challengers

Make sure your inspiration is real; it looks like that one at least has been photoshopped.

 

[Vigo The Carpathian]

Unless Steel Bent Customs really felt compelled to photoshop it from multiple angles and then pretend they actually built it, I'm pretty sure it's a real bike.

http://s1085.beta.photobucket.com/user/mundy888/library/1980 Honda CB750 Neck Tat

The dunlop logo was obviously painted, but that's in no way relevant to what I'm asking anyway.

 

[bcware]

It is photoshopped from multiple angles.

People have made similar loops on the frame; there is nothing stopping you from doing it. All you have to do is chop the rear off just after the suspension mounts. It will look good.

This thread has a lot of photos to look at: http://www.xs400.com/forum/showthread.php?t=4476

 

[Charles]

Do you have access to a tubing bender? If not, track down fabrication shops, even muffler shops and ask them to bend you a hoop, then bend each part where it will be welded to the frame. Or, you can forego the hoop entirely and use your pan to create the upward bend for your seat. As you can see here, no seat hoop, it's just chopped and the seat itself has a subtle upturn.

 

[elvisrock]

Hi,

I made my loop out of three pieces as I wanted it to be angled upwards and to keep the curves flowing without any straight section, then had them welded together, I'm really happy with the result.

 

[Vigo The Carpathian]

Thanks for everyone's help!

 

[CLovin]

Hope no one minds my dead thread revival, but is it still structurally aound if the xs does not have a loop on there adter it has been cut? I have had my bike for around two years and one of the PO's chopped that off prior to my owning it. In any case i have been riding since owning it without any real concern. So now i am curious.

 

[J-Rod10]

It is a weaker frame without being rebraced after cutting the tail end.

 

[CLovin]

I see, so it potentially could fall apart from under me?

 

[J-Rod10]

Doubtful. It will have more flex though. I always rebraced mine.

 

[CLovin]

Thanks for the help!