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Author Topic: HM300 verses HM 341 exhaust  (Read 5738 times)

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Offline 4 BANGER

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HM300 verses HM 341 exhaust
« on: May 04, 2011, 12:56:29 PM »
I have been hunting for a set of pipes for my 750 k1 and have found a set of 341s.
Rumor has it that they are more restrictive than the 300 but how restrictive are they?
- Will it effect performance?
-Will I have to re jet?
-Should I wait for a set of 300s?
Any info would be great.

  Thanks
« Last Edit: May 04, 2011, 04:21:13 PM by 4 BANGER »
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Offline guitarkev66

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Re: HM300 verses HM 341 exhaust
« Reply #1 on: May 04, 2011, 03:38:21 PM »
I ran 341's on my k1 for about a month or so, while looking for 300's.  The bike ran good with the 341's(so I thought).  Once I put the 300's on holy sh%$ a totally different bike.  Not only did it sound better but it had allot more power in the higher rpm range, oh yeah and no more black spark plugs. Just my opinion!
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Offline fire113

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Re: HM300 verses HM 341 exhaust
« Reply #2 on: May 04, 2011, 03:46:18 PM »
...with HM341 main jet should be 120(K0-K2) with HM300 ~140(K0-K2).

Be careful guitarkev66 don't toast Your engine  :o
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Offline 4 BANGER

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Re: HM300 verses HM 341 exhaust
« Reply #3 on: May 04, 2011, 06:25:38 PM »
Well that kinda sucks. Pipes are had to find, and I love the top end.
The old girl runs so nice at high speed.
I have a set of headers on it now but to finish the restoration I will
need pipes. The last step.
OK anyone know were to get a set of 300s? New or used.
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Offline Gordon

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Re: HM300 verses HM 341 exhaust
« Reply #4 on: May 04, 2011, 06:29:10 PM »
New HM300's are available from David Silver, but you gotta want them bad.  Like 1200 bucks bad. 
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Offline andy750

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Re: HM300 verses HM 341 exhaust
« Reply #5 on: May 04, 2011, 06:33:24 PM »
Quote from: fire113 on May 04, 2011, 03:46:18 PM
...with HM341 main jet should be 120(K0-K2) with HM300 ~140(K0-K2).

Be careful guitarkev66 don't toast Your engine  :o


Not on my K2. It has HM300s and 120 mains - runs great!

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Offline Johnie

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Re: HM300 verses HM 341 exhaust
« Reply #6 on: May 04, 2011, 07:29:44 PM »
New 300's can be had from your HONDA dealer too. Pricey...but just tell the wife it is a 1 time buy.
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Offline 736cc

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Re: HM300 verses HM 341 exhaust
« Reply #7 on: May 05, 2011, 04:26:12 AM »
341 pipes can be modified by drilling-out the internal baffles w/ a long 1/4" drill bit (it won't be visable). Then they sound and perform pretty much like HM300's. The end caps can be modded, too w/ a few minutes of work (the 341 pipes look wierd w/o end caps). Jet 40 pilots w/ 120 mains, and swiss-cheeze the airbox bottom half for better breathing.


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Offline Spanner 1

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Re: HM300 verses HM 341 exhaust
« Reply #8 on: May 05, 2011, 05:55:34 AM »
Yep, that's what I did... ( K1 with 341 pipes ), drilled-out the last 2 baffles and kept the exhaust tips with 120 mains and stock airbox
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Offline 4 BANGER

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Re: HM300 verses HM 341 exhaust
« Reply #9 on: May 05, 2011, 11:52:56 AM »
Thanks a lot guys. I did price out new pipes
and wow. Me thinks I will modify and in stall
the 341s.  My wife loves the bike and would
bit the bullet for pipes but its the old man. He
would like to get a new riding mower.
So many toys, an so little cash.
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