Half Metal Intake Boots?

Been compiling a list of all the work I want to do to my XJ and it looks like I might need new intake boots. I haven't done a vacuum test but there are some cracks so its a possibility. Seeing as the OEM replacements run $60+ would a metal version be possible? Something like this. I know this would not be compatible and isn't anywhere close to the right size but if you could find one with the right dimensions on the engine size, the right diameter, and drilled out a hole for the vac port (I think that's the name).

If the rubber cracked or broke you would only be replacing a small section of cheap rubber hose you can find anywhere instead of a rubber boot that might be hard to get a hold of in the future.

Some issues with this I see right away are the limited space between the engine and carb to fit this and the seal on the engine.

Assuming you could find a ready made part that could be repurposed with some elementary modifications what is everyone's thoughts on this?

 

if you went to metal bases and then a rubber coupling to carbs it may work. I have seen a suggestion like this. where the intake boots are metal with a short hose to mt carbs.

 

This is the exact setup on my FZR1000. Space, size, etc are different, but I wonder if some bike has a part that can be repurposed.

 

The Yamaha XTZ750 Super Tenere has metal intake stubs. Might be able to get ones off another bike that can be adapted.

 

How about these? What about the stubs for the vaccum line to the tank and balancing the carburettors?

https://www.mikunioz.com/shop/alloy...0mm-spigot-with-slotted-holes/?v=79cba1185463

 

That's really cool! I figure they could simply be drilled for a brass vacuum nipple and brazed in.

 

I liked them too that would be a good way to secure the vacuum stubs. Just checked my original inlet stubs they are at an angle that might cause a problem?

 

I wouldn't think angling the hole would be an issue, as long as you had proper machinery to set up the drilling so it's stable and accurate.

 

Great well they are a good solution, I might get a set once I sort everything else out.

 

Ooh, they have some for my 550! https://www.mikunioz.com/shop/mikun...spigot-od46-59mm-stud-centres/?v=7516fd43adaa

 

Yes they would look great on your bike. Cool.

 

https://www.mikunioz.com/product-ca...folds/two-bolt-flanges/page/2/?v=79cba1185463

 

I think I saved my original boots. Looks like figuring out the offsets will be a thing.

 

Yes that is what l meant earlier.

Yamaha stub is at an angle. Alloy stubs are 90 degrees to their flange which bolts onto the cylinder head so they would not line up as you know.

 

ha, I thought you meant angle of the vacuum nipple. duh!

 

No that is the easy part to sort cause you can weld lol.

 

Oh, sure, if I had a welder!

 

Sent the company an e mail question about a solution to the intake stub angle. Hopefully there is a solution.

 

Company response. Sorry these flanges are unique to yamaha and they will be your only source for replacements especially if staying with you present carbs.

Shame they don't have a solution for our XJ bikes.

 

I noticed they had offset boots: https://www.mikunioz.com/shop/mikun...apered-id-40mm-offset-boot-id/?v=7516fd43adaa

 

They have a 13mm offset.

 

likely Yamaha designed it and they wont modify it because of a license, and they sell more to yamaha.
maybe if you wanted 100k of them they would work with you.

 

They aluminium ones look good too it is a pity there is not a solution because of the angled Yamaha inlet stubs. When I saw them I knew they would probably not fit off the shelf.

 

that would be to lucky to find off the shelf. or yamaha would be selling it as a replacement

 

True.

 

I think its going to depend on the XJ. My '81 XJ750 doesn't look like it has that angle after taking a quick look. Is there a place you guys get the dimensions for the OEM ones or just measuring yourself?

As for the vacuum lines, if you drilled a hole straight down and put some sort of fitting on there that you could attach a hose onto with a hose clamp it would work fine.