How to seal carb to inlet stub??

[Doofus]

Could anyone advise the best sealing method for my Bing 54 onto an MC5 inlet stub? The fit is not good enough with the bike I have and a previous owner placed a thin metal "lining" inside the carb. It must be source of an air leak I've been trying to cure, so I'm looking for any other methods or materials used. Thanks for any advice.

[G Ellis]

You need a carb sleeve adapter.

[Doofus]

Difficult as the carb fits directly to the stub and there's little room to do anything different from what KTM intended. \I ned a fuel proof sealant I think as the gap I need to seal is microns thin.

[KJDonovan]

Dave,

Get a piece of 1.5mil heat resistant Mylar.  Cut it to the correct width coil it around the intake spigot and hold in place with a tiny dab of tape.  I have done the same for sloppy fitting carb to intake connections in the past and it works fine.

Thanks,

Kevin

[Doofus]

Thanks Kevin. Top tip!

[454MRW]

I use the Chrome metal duct tape tape to seal exhaust pipe to silencer slip fit joints that are a little loose. It should work well in this application also and it has an adhesive backing. I use it a lot to insulate exhaust pipes to plastic RM Suzuki are boxes which are prone for burning. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Penton
1976 MC5 400
1978 KTM 78 GS6 250
L78-79 MX6 175-250 KTM's
1976-78 125-400 RM's
2007 CR125R Honda
1977 MC250 Maico
2017 KTM Freeride 250R

[Doofus]

Yessss!!!! The mylar tape worked. Great tip. Just back from her first decent test run. Nothing fell off or puked.
 I'm running a new 2.74 main jet and needle, 2nd notch, which does let her rev out with some decent power but no afterburner effect that I had before. Just glad to have got her going for now. I'll play with other jets later once I've looked at the plug tip.
 Thanks All.

[skiracer]

And where do you find heat resistant Mylar?

quote:Originally posted by KJDonovan

Dave,

Get a piece of 1.5mil heat resistant Mylar.  Cut it to the correct width coil it around the intake spigot and hold in place with a tiny dab of tape.  I have done the same for sloppy fitting carb to intake connections in the past and it works fine.

Thanks,

Kevin

1976 MC 5 Original Owner
1976 Penton 175 XC

[KJDonovan]

James,

I usually grab it from my wifes sewing stuff. I would guess it's available in places other than sewing stores too.

https://www.missouriquiltco.com/shop/detail/27694/quilters-rule/-/heat-resistant-mylar-template-sheet-10-x-12

Thanks,

Kevin

[skiracer]

Thanks Kevin!

quote:Originally posted by KJDonovan

James,

I usually grab it from my wifes sewing stuff. I would guess it's available in places other than sewing stores too.

https://www.missouriquiltco.com/shop/detail/27694/quilters-rule/-/heat-resistant-mylar-template-sheet-10-x-12

Thanks,

Kevin

1976 MC 5 Original Owner
1976 Penton 175 XC

[Doofus]

I got a 10 m length of foil backed heat resistant mylar tape from an ebay search. It was very cheap and usually used for hydroponic greenhouses. See link https://www.ebay.co.uk/itm/HYDROPONICS-MYLAR-SHEET-TAPE-HEAT-MOISTURE-PROOF-SELF-ADHESIVE-GROW-ROOM-TAPE/181313160821?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649