I’m purchasing a 2017 freewheeler (M8 107) next week. It looks like both sets of slip-ons I had on my EVO (tunable hookers and CFRs) will physically fit the new FW. My question is are slip-ons made by the SAME manufacturer designed differently for different size engines or is it just about physical fit when they ask you the make, model and year. I understand that each manufacturer has their own internal design and different slip-ons perform differently depending on the engine, but didn’t know if slip-ons were interchangeable between engine sizes as long as they fit.

The engine is staying stock and I’m not de-catting.

Any input or thoughts would greatly be appreciated.

Thanks,
Ron

 

I am sure there are possibly some out there designed for each specific engine... But, if you look at someone like V&H, they have one quiet baffle that fits their exhausts... all their exhausts.

I honestly think they ride one internal design, and try to make the mounting as universal as possible. At least that's what I'd do.

Back in the day, you bought 1 3/4" drag pipes for Sportsters and 2" for Big Twins... But, that was when BTs were 80"...

 

Good point on the V&H baffles. That all makes sense, what was really confusing me was I sent an inquiry to a couple of different sllip on manufactures to see if they made mufflers for the 2017 freewheeler and they said not yet, but I've got two sets here in the garage that sure look like they will so figured it must be something on the inside. Harley dealers are little help as they just want to sell their street cannons. Thanks! Ron

 

I thought the 2017 touring models with M8 use different diameter header pipe on each side. I dont own one but recall reading this somewhere

 

I'm not sure about the touring or triglides models but I finally get the harley service manager to confirm that both pipes coming out of the cat on the 2017 freewheeler were both 1 3/4. But I'm not taking any bets until I've installed them for myself!

Thanks,

 

You are correct , nothing pre 2017 will fit a M8 based bike. Other issues the OP may want to be aware of there's a lot of back and forth with dealers and the moco about voiding the drive train warranty if non harley supplied parts are used. Suggest you talk directly to your dealer about things before you spend money.

 

Yes, I walked out on a deal because of their stand on non harley parts voiding the warranty, I asked them twice if they were really sure... they said yes and I left. Went to next dealer 'owner' who said any slipon would NOT void 2 year warranty. That's where I bought... other dealer manager called two days later and said they had new info and that it would be ok.... told them I appreciated the follow up but it was too late. SO much misinformation even within their own team. Most 'sales' people really don't understand their custom base or the bikesas well as they should, they just read the glossy brochures. just my opinion.