[SMLE535]

Okay, the part number for the exhaust pipe adapter is from Autozone.
17526
ni exhaust solutions
Adapter
1-7/8" ID x 1-3/4" OD
$2.99
Red and white label.

I fitted Bills ACE airbox a few years ago ... with zip ties lol

Now got ACE valves and cams from Bill, will be fitting them shortly.

A question about the exhaust pipe adapter. Tom mentioned this to me a few years ago, and I have forgotten sigh. I have the Hitchcock header. Should I get this bit of kit and shove it in the top of the header? Making the inner diameter less at the top than the bottom? Sorry, I am an ignoramus

[Softlysoftlycatcheemonkey]

   I'd read this thread a couple times in the past and my memory is foggy, but it seemed like you need a short pipe whose outside diameter is an easy fit into the exhaust port end of the ( Hitchcock's ) header pipe and whose own internal diameter is equal to but no less that of the exhaust port of the head. Since it's not likely to work the found pipe to fit into the header and around that sharp bend you cut/grind the short pipe so that it fits as far as possible into the header without interfering with the outgoing gas's path through the bend; you should end up with a roughly wedged shape, but tailor for easy gas flow around that bend as you see fit. I believe once the short pipe is fit as far as possible into the header you can cut the short piece so it's flush with the header: not too short, not too long, but just right, and since the exhaust port opening is smaller than the header  the short stub will be held in place when the header is mounted to the head. Like a stepped header this will  keep exhaust gases moving out quickly and discourage their reversion back into the exhaust port. This surgery procedure has been done by experimenter Otto_Ing/derottone with success and he could walk you through the subtleties.

[Softlysoftlycatcheemonkey]

...and I also want to acknowledge that this thread and the gentlemen who spitballed and worked throughout it agitated ( if thats the appropriate word ) my own brane to ( someday ) remove and remake the stock airbox and add a velocity stack, foreward facing air intake, stepped header, and generally see the gt for what is.

[gizzo]

Post #21 in the What did you do to your continental gt today? thread has a pic of otto's reducer for his motad pipe. I made a similar one for my H header, welded to the reducer ring that comes with the header. It reaches the tp bens and has a notch cut out to fit past the o2 sensor bung.
https://forum.classicmotorworks.com/index.php?topic=23044.15

[Arschloch]

Anyhow you build it, if you stick to the principles and rule of thumb figures provided it will do well. Longlivity and reliability of the construction is the buiders responsibility. 

[gizzo]

Post #21 in the What did you do to your continental gt today? thread has a pic of otto's reducer for his motad pipe. I made a similar one for my H header, welded to the reducer ring that comes with the header. It reaches the tp bens and has a notch cut out to fit past the o2 sensor bung.
https://forum.classicmotorworks.com/index.php?topic=23044.15

LOL tp bens = top bend 😂

[SMLE535]

thanks gents, appreciated

[gizzo]

thanks gents, appreciated

No worries.

Also, you're riding a Pantah? Good choice. Love mine.

[SMLE535]

it was my first bike in 1987 (tut tut skipped the 250 lol). Changed it for the roundcase bevel drive GT750 in 1991. Changed THAT for the 996 in 2010, which got stolen by some dirty rotten ba**ards in 2019, and now have the 535 since then. And loving it, its idiosyncratic - thats nothing to do with idiots btw lol

speaking of which, I AM an idiot. Looking at the various posts, and Ottos picture of the sleeve, and Ace.cafes part number 17526 SureBilt 1 7/8in ID X 1 3/4in OD Exhaust Adapter, and unable to actually GET the autozone stuff, they look different. Ottos looks like a straight pipe, not a reducer with different OD at either end.

This looks like it fits the ace.cafe description, but I cannot see how it fits in the header (and doesnt look like Ottos)

[Softlysoftlycatcheemonkey]

    You could ask by contacting him directly on the forums at https://westerncyclesupply.com/ or through his business partner on this forum Guaire.

[gizzo]

it was my first bike in 1987 (tut tut skipped the 250 lol). Changed it for the roundcase bevel drive GT750 in 1991. Changed THAT for the 996 in 2010, which got stolen by some dirty rotten ba**ards in 2019, and now have the 535 since then. And loving it, its idiosyncratic - thats nothing to do with idiots btw lol

speaking of which, I AM an idiot. Looking at the various posts, and Ottos picture of the sleeve, and Ace.cafes part number 17526 SureBilt 1 7/8in ID X 1 3/4in OD Exhaust Adapter, and unable to actually GET the autozone stuff, they look different. Ottos looks like a straight pipe, not a reducer with different OD at either end.

This looks like it fits the ace.cafe description, but I cannot see how it fits in the header (and doesnt look like Ottos)

Yeah, I don't think that's going to work. Also, the Autozone adapter mentioned is unlikey to work either seeing the 1 3/4" OD is smaller than the 1 7/8" ID. You'd need to turn it inside out.

I was lucky enough when I made mine that I had a length of perfectly sized exhaust tube laying around that is 35mm od, 32mm (ish) ID. That was the exact same ID as the exhaust reducer ring that came with the H header and it fit perfect. Once you know what you need, the local exhaust place will give you an offcut for almost nothing.

I don't really want to pull my pipe off but if it'll help to get you a picture or 2 and some measurements, I'll take one for the team.

Too bad about the 996. That's funny about your Pantah being your first bike: mine wasn't my first but it was pretty early in my riding story it came along. I bought it in about '93ish? I wa a dumb kid and treated it really badly for a while there, when it wasn't worth anything. I take a bit more care with it these days.

[SMLE535]

Thanks Softly, on it

Thanks gizzo, please don't take one for the team

[Guaire]

" You could ask by contacting him directly on the forums at https://westerncyclesupply.com/ or through his business partner on this forum Guaire."

I just looked at this today, Mar 19, 2023! You can get ACE Motors contact info at:
https://www.acemotorsonline.com

Western Cycle Supply is run by Tim Hirdler, not me. The site an excellent source of parts and has a forum on the site. I've known Tim since the days of Classic MotorWorks and buying iron barrel parts through him at CMW.

I just wanted to clarify who's who in this zoo. I still use Western Cycle Supply for parts. It's a good source for current Royal Enfield parts as well.

My Bullet B5 came as a fix up bike from Cycles of Silver Spring. Most of the 'fix up' parts came from Western CS. This Bullet UCE became a test bed for our products.This bike is on this forum as it now is running the ACE Motors Clubman Kit 2 head and other special parts.
Regards,
Bill G.

[Softlysoftlycatcheemonkey]

    Good, good. I'm glad this forum is still operating, and without all the extra noise/repetition concerning tire choice, ebay seats, plugin tuning options for the engine, etc. of models in production; one can participate without "stepping on too many newbies". It's been awhile, but I think Ace.Cafe/Tom Lyons is available on the Western Cycle forums, and has occasionally popped up here. And you, Guaire, I'd be curious about what you still do for the 535; do you have any airbox covers left? Is the cnc head still being produced ( even with today's higher costs )? I'd have messaged you about these, but I think your answer will be of use to others...and the airbox cover would be a definite buy from me.

[Arschloch]

At least RE saved the world of affordable motorcycling, hopefully soon to be rewarded by mandatory sales of only electric bikes.