After being told by my wife that she wasn't going to ride with me again until I got rid of " that loud a** pipe" and being told by the rest of the family that they were going to take a no confidence vote on me being the leader of the pack I have had to take off the HMF. And..... I have to agree with them. It had gotten so loud that it was annoying to be around.
I had been reading some post about modding the stock pipe. Some talked about drilling holes and one even suggested that blasting the packing out with a pressure washer would give it more power....???
SOOOOO..........I pulled the old stock pipe out of the shed . I cut the weld of the end cap and ground out the plug welds that held in the collecter for the silencer. I also ground out the plug welds for the turbine. I pulled out the silencer and turbine. I cut the silencer off the end cap . Then I lengthened the finns on the turbine using a cuttoff wheel and open them up by changing the pitch with a pair of pliers. Behind the turbine is the baffle chamber. I left it intact but I did drill 12 3/8" holes in it inline of where the headers inter the canister. This will help it flow more but keep the sound level down. I then inserted the modified turbine and plug weld it in it's original position. I welded the end cap back on minus the silencer and collector. Then I welded the snorkel on. I gave it a thick coat of 1500* exhaust flat black and installed.
MAN>>>>THIS THING SOUNDS 100% better. It has a very deep throaty tone and will not ring your ears like the HMF. It's a totally different sound then the HMF ever made. It sounds like a deeper throatier Muzzy.
Performance wise it brought back allot of the bottomend torque and doesn't revout as quikly as the HMF. It restored some of the back pressure the motor needs to produce good torque. Feels really strong and the jetting seems to be about right.
After doing this I would have to say this is one of my 3 top favorite mods. The others being the Moose/6* key combo and removing the swaybar. And the HMF being the worst...A big waste of money. IMO
Later on today I'll have some pics of the process posted .
__________________ BF750 Built For Business
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Wow - sounds great! Looking forward to seeing the photos... do you think this would work for the BF650i? What is the 'removing sway bar mod you mentioned?
I'm new to the scene and looking for tips - I can't believe how much I like my 650i!
thanks,
CDL
__________________
2007 BF650i Black
Warn 2.5
26" IPT XTR's
I've made one more change at the request of the little lady( What would I do without her??) She said it sounded good but she hates it being in her ear sooooo....I cut the snork off flush with the end of the canister and secured the endcap turn down to it with hex head drill point screws . Sounds even better!!!!! The snork gave it a "rattatat" sound now it's a nice clean rumble. Being that the only reason I put the snork on the HMF was to try protect the packing, I don't think it will be missed. Good thing about this is it can be washed out easly. Just pull the plug and flush it out.
__________________ Brute Force 650 sra
25" Mud B!!ch, ITP Type 7, stock yellow secondary,
Maroon primary, BF 750 clutch cover, KFX 700 cylinders
82mm Wiseco 11.5:1 pistons, stock cams, Dynatek CDI ,
VFJ UPP intake, Fan switch, K & N filter, HMF full exhaust
Warn XT25 winch with 50' syn rope KFX V-Force 700
VFJ stage 3 clutch, Almond primary, Quadboss full skids, Fan switch, K & N Filter with
Outerwear, 12 hole mod, Muzzy Pro with stainless oval can, Spark plug boot mod, ASR SS
Front Brake Lines, VFJ UPP intakes, Razr 2's on ITP baja's, Orange PowerMadd Handguards,
Maier carbon fiber hood, H.E.P Taillight, AC racing front bumper, AC Pro peg nerf bars 2005 Brute Force 750 to many mods to list! http://i31.photobucket.com/albums/c3...s/SANY2301.jpghttp://i31.photobucket.com/albums/c3...SANY1909-1.jpg
Wow - sounds great! Looking forward to seeing the photos... do you think this would work for the BF650i? What is the 'removing sway bar mod you mentioned?
I'm new to the scene and looking for tips - I can't believe how much I like my 650i!
thanks,
CDL[/b][/b]
This should work on the 650i.......Removing the swaybar is a mudders modification. I lets the rear be truly independent . If you like fast trail rides and cornering this wouldn't be for you
You ended up doing almost exactly what I ended up with after 3 rebuilds of my stock exhaust. Only difference is I also drilled holes in the turbine. Sound is perfect, nice low throaty sound without alot of volume. I think it acutally flows BETTER than the HMF because the bike has taken a much larger jet than HMF reccomends. You cannot beat the price, and it's great when something free acutally works better than the aftermarket counterpart.
You ended up doing almost exactly what I ended up with after 3 rebuilds of my stock exhaust. Only difference is I also drilled holes in the turbine. Sound is perfect, nice low throaty sound without alot of volume. I think it actually flows BETTER than the HMF because the bike has taken a much larger jet than HMF recommends. You cannot beat the price, and it's great when something free actually works better than the after market counterpart.[/b][/b]
At first I thought about just drilling holes all the way through it but after I got the silencer out and shown my flash light into the turbine to see what was back there I decided on pulling out the turbine and opening it up some and then drill the holes where some of the exhaust would have a straight shot out. You can see in the pics that I drilled one hole then stopped The turbine actually directs the exhaust towards the center of the end cap so it doesn't just hit the back of canister and bounce around.
My biggest gripe about the HMF was it didn't hold up to the mud.......Of course they have been trying to tell us that.
STOCK EXHAUST MODIFIED AND HMF GONE........
Linear Mode
