OzVMX Forum

Clubroom => Tech Talk => Topic started by: Kenneth S (222) on July 06, 2014, 10:01:42 pm

Title: Exhaust Pipe Design Advice
Post by: Kenneth S (222) on July 06, 2014, 10:01:42 pm

Hi Guys,

I am fitting a set of Piggyback shocks to my RZ and I need to create some clearance from the exhaust pipe. If I do what I have illustrated on this image in white, will it have any negative effects to how the bike runs?

(http://i1213.photobucket.com/albums/cc468/24HourMerchMan/Piggyback_zpsd0969be7.jpg)

Title: Re: Exhaust Pipe Design Advice
Post by: gdr on July 06, 2014, 10:04:11 pm

Less bends = Better flow

Title: Re: Exhaust Pipe Design Advice
Post by: marshallmech on July 06, 2014, 10:20:42 pm

The piggy backs on the 80 model go with the piggy back to the front of the bike can you fit them that way

Title: Re: Exhaust Pipe Design Advice
Post by: Lozza on July 06, 2014, 11:02:05 pm

Quote from: KJS222 on July 06, 2014, 10:01:42 pm

Hi Guys,

I am fitting a set of Piggyback shocks to my RZ and I need to create some clearance from the exhaust pipe. If I do what I have illustrated on this image in white, will it have any negative effects to how the bike runs?

(http://i1213.photobucket.com/albums/cc468/24HourMerchMan/Piggyback_zpsd0969be7.jpg)

Will not make any difference at all

Title: Re: Exhaust Pipe Design Advice
Post by: Kenneth S (222) on July 07, 2014, 07:05:47 am

Quote from: marshallmech on July 06, 2014, 10:20:42 pm

The piggy backs on the 80 model go with the piggy back to the front of the bike can you fit them that way

No I can't. It hits the frame unfortunately.

Title: Re: Exhaust Pipe Design Advice
Post by: HVA61 on July 07, 2014, 08:11:41 am

Almost no difference providing you have sweeping bends

Title: Re: Exhaust Pipe Design Advice
Post by: bigk on July 07, 2014, 09:38:40 am

It's a simple fix Kenneth, just move the muffler back to clear or copy a 1980 RA250 muffler (which will fit with no mods). Done it many times with no noticeable difference to power.
Cheers,
K

Title: Re: Exhaust Pipe Design Advice
Post by: GMC on July 07, 2014, 10:10:28 am

It might depend on the brand of shock and the size of the piggyback but I found just moving the muffler body rearwards wasn't enough.

(http://i15.photobucket.com/albums/a393/gmcloa/Mufflers/CR250-79-muffler-2_zpsd02c2ca3.jpg) (http://s15.photobucket.com/user/gmcloa/media/Mufflers/CR250-79-muffler-2_zpsd02c2ca3.jpg.html)

Title: Re: Exhaust Pipe Design Advice
Post by: HVA61 on July 07, 2014, 10:32:45 am

That's art

Title: Re: Exhaust Pipe Design Advice
Post by: smed on July 07, 2014, 10:51:48 am

I hung my muffler off the seat bracket & added a short straight section between it & the pipe,moving the muffler backwards & clearing my piggy backs,I took the spring off one shock,fitted it to the bike then checked clearance at full wheel travel
 ;)

(http://i1266.photobucket.com/albums/jj529/smed45/1fe3606a-92da-430b-b0de-017f4781a2fe_zps61f764ee.jpg) (http://s1266.photobucket.com/user/smed45/media/1fe3606a-92da-430b-b0de-017f4781a2fe_zps61f764ee.jpg.html)

Title: Re: Exhaust Pipe Design Advice
Post by: Kenneth S (222) on July 09, 2014, 07:27:50 pm

Thanks Guys,

Thanks guys, much appreciated. The bracket on the muffler I have is off center, with the bracket closer to the rear of the bike. My plan was to flip it around so the long end was toward the rear, swap the end plates, and have the new section of pipe made up as a curved piece. Looks like I am on track.