Do they use them on any of the newer big singles ?
What’s the price ?

https://delkevic.com/

They are made for the S40.

I put a Supertrapp on my first one.
Awfully expensive
Not worth it
I should have put a Dyna on it and used the money for gas and tires.

rangeshooter wrote on 02/25/19 at 17:51:53:



If you change the exhaust and it doesn't require rejetting, then the only performance gain you achieve is the tiny amount from reducing the weight in your wallet.

i have the long slash cut one, i have not rejetted and it does not pop more then with stock "little at shutoff and closed throttle"
its pretty loud when you get on it, but at cruising speed my wife can talk to me and i can hear her.  if i remember correct it has several different settings for the loudness by removing adding a deflector in the nose of the muffler.
its also about 1/3 the weight of the stock muffler, it fit perfectly.  
im pretty happy with it, wished it was cheaper.  
not sure if the link will work but this is a very short youtube of my bike with the exhaust fitted. someday ill make a better one
https://www.youtube.com/watch?v=xc0pw__WKKI

TheBabyDerp wrote on 11/02/24 at 06:10:59:


Dredging up old posts.  One of my favorite pass times. I’m not sure anyone has dropped the money on a Delkevic muffler for the Savage.  

As I am to understand it, and I could be wrong — A shorter overall exhaust increases torque at higher RPMs, but a longer exhaust increases torque at lower RPMs.  I think Lancer did some playing around with this.

DragBikeMike’s Muffler Shoot Out on his souped up bike has a lot of good information.  The big takeaway for me wasn’t the length of the exhaust, but rather, the puny 1.3” diameter of the header pipe and “broken dog leg” exhaust port restricted flow.  I think Mike and others have found that 1.3” is too small and 2.0” is too big.  The sweet spot being 1.5”-1.625” ID.  Finding that diameter pipe has proven elusive to me unless you want to pay big bucks and have a custom header made.  MAC Performance may have made one when they were in business, but finding a decent used one hasn’t surfaced anything.

Go with a Dyna is my suggestion.   Self-serving sales pitch — I’ll have a really nice pair in my possession in about a month.  My son-in-law picked them up for me.  I just need to go get ‘em around Thanksgiving.  I really like the way mine turned out especially with a 6” HD heat shield and adapter.

I chose to use the 1.65” ID x 1.75” OD pipe, with a 30” length.
The reason is because of Ed.  Ed started building headers in the 60’s, and based his choice of pipe size and length on drag strip results.  With years of hands on experience he put together a chart for selecting the size needed for a cylinder of a given size and power level.  For our engine and its power level capabilities the header pipe size is best at 1.5-1,65” ID.   The length of the pipe at 30” is generally accepted for engines similar to ours, and varying the length can move the peak power up and down the rpm range.
Ive used a 1.65” ID pipe for several headers, usually with 30” length, however my current pipe is about 33”.  When making this pipe the last 6”  of it was distorted a bit so  cutting it 30”  would have left the end unable to make a good fit and seal with a muffler…so it’s longer.
So Ive used the 1.65” tube for years, I made my first one in the early 2,000’s, and I like it a lot.
When MAC first came out with their 2” pipe and muffler they held a contest on this site, and I won the drawing.  I installed the set, rode it for a while, could not tell a performance difference, maybe less.
I think DragBikeMike used a larger pipe during his series of engine testing.  I believe he may have had better results.
Another resource I’ve used is a book on Engine Performance by an Automotive Engineer, whose career was with the big 3 US auto makers.  He designed engines.  He said the internal volume of a muffler should be the same volume in a cylinder, and the Dyna muffler we use so often is pretty close to that volume.  An R&D test muffler I got years ago works great on my engine. (Yep, it was designed for HD’s).  It is quite loud though.  (Versey can tell you about that).  They work well and make good sound.
The authors stated primary goal when building an engine is to maximize Efficiency.