| Author | Message | ||
     Crazyhawk99 |
I finally got around to installing the HMF slip-on I bought months ago. It was NOT a fast process. Not only is the OEM muffler a pain to remove, but the HMF was not exactly a piece of cake to bolt up. I like to never got the mid-pipe to header pipe to slip together. The header pipe mount point didn't take into account bolting up the oil cooler lower mount, so I had to mount it shifted over 1/4 inch to the left (as view from the saddle). Then I fire it up and I was startled by how loud it was. Granted the garage door was closed, but I live in Germany and it is Sunday night so I dared not open the garage door to try it. I researched via forums before buying it on several sites and at the time, the word was it was quieter than the FMF & Jardine. At this point I really have to wonder how loud they could be. Anyway, I got off track. With the HMF came a round screen thing, but it isn't mentioned in the instructions. Anyone know what it is for/where it goes? | ||
| Mrbikle |
i believe that is the quiet core... I have a HMF as well and it is much louder at idle then it is under load or cruising... FWIW | ||
| Jules |
It's a spark arrestor: http://hmfracing.com/tech-resources/install-quiet- core--spark-arrestor | ||
| Crazyhawk99 |
Spark arrestor makes sense, but when I was putting the pipe on I couldn't find anywhere that it would fit. Do you know if anyone has tried the quiet core on the HMF and if it actually works at all? | ||
| Bob_thompson |
"It's a spark arrestor" "Spark arrestor makes sense" WTF guys, Why would you need a spark arrestor on anything except a two stroke thats running rich. If you are shooting sparks out the end of the muffler you ARE waaaay too rich. Its an HMF gimmic, IMHO. Silencer inserts are out there that REALLY work. Do the research. With all due respect, and sorry about being blunt but I dislike internet speculation. Get the facts. Bob | ||
| 1_mike |
By design...it's very similar to the Jardine and FMF. Just the perforation size may be a little different, and that's not gonna make a ton of difference. As far as the installation...I heated the HMF collector and spread it to better match the Buell header spacing, rather than squeeze the header tubes together. Mike | ||
| Tbones1125r |
I agree that it's not a piece of cake to put on but it makes an improvement to performance and is not terribly loud...I like it so far... | ||
| Bigschwerm |
Love my HMF...i have the HMF specific tune downloaded and makes a world of difference...spark maps and fuel. | ||
| Crazyhawk99 |
Bob, First of all, when I said "Spark arrestor makes sense", what I was saying was based on what the item looks like (conical screen), that description fit it perfectly. Had you taken the time to click on the link that Jules provided, you would have seen that indeed it is marketed as a spark arrestor. I don't know why or if it needs one or if it works. Just the facts. You dislike "internet speculation" and frankly there was no speculation. Like it or not, it IS a spark arrestor. I dislike people that reply to threads with nothing constructive or supportive to say. Sorry if that came across as blunt, but I had a frustrating day wrenching on the bike, posted a question afterward and I get your reply. Talk about a mood breaker. | ||
| Crazyhawk99 |
Big, When you say you have the specific tune downloaded, are you referring to a PC V? Thanks for the input! | ||
| Bigschwerm |
Crazyhawk99.... its not the PC V that only controls fuel its a custom tune made for the pipe...actually i gave the person my whole slip on when i deployed overseas and the made the tune. send me a email an d i can give you the info. rschwerma76@yahoo.com | ||
| Jules |
With all due respect, and sorry about being blunt but I dislike internet speculation. Get the facts. Bob I did... And as has been pointed out already I even provided a link to the manufacturers website. Personally I think you're the one speculating with the whole "Why would you need a spark arrestor on anything except a two stroke thats running rich" which isn't so much speculation as total bollocks... | ||
| Crazyhawk99 |
Big, Email sent. I have an EBR Race ECM that I will be installing after work (time allowing), but I am always interested in options. I really like the rumble of the HMF. Sounds kinda like an old muscle car, but I do wish the rumble was a bit quieter. I am stationed in Germany and the Europeans aren't nearly as tolerant of noise as Americans. | ||
| Jules |
I am stationed in Germany and the Europeans aren't nearly as tolerant of noise as Americans. Damn - I'd be insulted if that weren't so true  Where in Germany are you? | ||
| Crazyhawk99 |
Jules, I live outside of Heidelberg. I'll be passin' thru the UK in June to meet up with some mates I met at the IOM last year, on the way to IOM this year. | ||
| Mountainstorm |
It helps to unbolt the front header stub from the engine when installing the HMF otherwise you have to pry it into place which is not the best way to proceed. Likewise you should have easily been able to locate the y-pipe mounting tab in the correct location (provided the front header tube was loose from the engine). When I ordered my semi-elliptical HMF they told me there was no quiet core available because "the exhaust was already so restrictive" talk about utter BS. Anyway the HMF is loud. It's so loud that despite enjoying a distinctive exhaust tone I am still considering putting something else on. It's especially loud at idle, and with the Apache Helicopter like idle of the bike it's not an entertaining loud, more like an embarassing loud. I doubt it is actually any less loud at throttle or in motion, it's just sending the shock wave away from the rider's ears is all. If noise is a concern the HMF is not the best choice. In fact I am not all the certain it even improves the performance of the bike, at least not without a recalibrated fuel map. (Message edited by MountainStorm on April 12, 2010) | ||
| Crazyhawk99 |
Mountain, I did consider loosening the front header. It would have helped, in hindsight. The collectors weren't a matchup. I ended up tying a rope around the headers and twisting it to bring them closer together so I could slip on the HMF collector. The main problem with the collector mount tab (at least mine) is there in not enough room to properly mount the lower oil cooler mount as it should be (shifted to the right of the frame mounts). As for the sounds, at idle it does sound good, but it does seem that it will be embarrassing. If I can't come up with some kind of silencer to make it quieter, I will yank it off. I agree with your thoughts on why some owners think it is quieter once moving. The noise is just behind you. As for a performance increase, that would be a bonus, but I am looking for a little soul, but not obnoxious noise. | ||
| Bob_thompson |
Crazyhawk99: "Had you taken the time to click on the link that Jules provided, you would have seen that indeed it is marketed as a spark arrestor. I don't know why or if it needs one or if it works." Bob: I did check out the link and I stand by what I said. "It is a gimmic" for a well tuned 4 stroke engine and kills air flow. With the small perforated holes it looses half the area of the tube(pipe)limiting air flow. Crazyhawk99: I dislike people that reply to threads with nothing constructive or supportive to say. Bob: What I said IS supportive if you had also taken the time to check out the few really great inserts for taming a real loud exhaust without sacrificing power. But a good exchange guys and we all kept it civil. Sorry you had a bad day Greg. Stay safe, Bob P.S. check out the inserts below, they really do work and are proven in racing applications: If there is not one small enough for your pipe, make one as I did or have it made. http://www.carchemistry.com/ http://www.afabcorp.com/AFCO_Dynatech_USbrake/merc hant.mvc?Screen=CTGY&Store_Code=Dynatech&Category_ Code=Mufflers | ||
| Mountainstorm |
The Y pipe tab should locate on the outboard side of the mount and the oil cooler support should locate on the inboard side of the mount. I'm looking at the HMF as a temporary experiment. Although I have grown used to the noise it's not exactly what I like. Dean Adams builds some slip on systems that have a nice sound, still might be a bit loud. You can also mess with the stock exhaust and get some more sound out of it. There are some posts on that archived here somewhere. Basically stick a drill bit into the exit tubes and make a hole in it where it bends without piercing the shell of the muffler. And there are some people who have cut open the stock muffler and altered the internals to make more sound, but I see no proof of more power from these simple mods. | ||
| D_adams |
I've done both, built custom and modified the stock pipe. The modified stock pipe didn't gain any power, nor did it lose any. | ||
| Crazyhawk99 |
Mountain, That is how I have the oil cooler mounted now, but that isn't how it was with the OEM muffler. As originally installed it is on the outboard side of the mount on the right side (view from saddle) and in inboard side on the left mount. Only potential problem now is with it shifted left, the top cooler mount doesn't line up. I wasn't able to slide it to the right to be captured by the stud/nut to secure it. I am thinking the HMF will be a short term pipe for me as well. I will be curious to see the results from the exhaust shootout and really hope they capture dB numbers cause I think there are a lot of riders concerned with noise these days. I will sacrifice some potential power for a pipe with a decent sound that isn't too loud. I don't think I am gonna mess with altering my stock muffler. Right now, that muffler is my fallback if I get beat up for a loud bike. I saw a thread somewhere of a place in the UK that is taking OEM mufflers and making it so you can change the volume via turning a ratchet. I am curious how they sound. Also, on the shootout thread, there is mention of a Rhinehart (sp?) muffler that I hadn't before heard of and it looks darn good, but as always, how loud is it...? Appreciate your input. | ||
| Froggy |
Because they are legally required to ride on US forest service roads and other public land? |
