Switching to Standard Exhausts

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evan_calgary
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Re: Switching to Standard Exhausts

#16 Post by evan_calgary » Fri May 04, 2018 4:46 pm

T.RexRacing wrote:You guy gotta remember if he's got US spec exhaust it's a catalyst pipe and jetting requirements are totally different than Euro or Canadian spec bikes. Lemme dig in my manual out in the garage for OEM numbers and I'll post up the results.

None of us have said anything about specific jetting numbers.

He has a manual and it seems like he knows his way around those numbers and letters.

catalyst pipes make it even more likely it is a jetting issue.

Go back to standard jetting and start from there. If you need help with jetting there is lots of info. on here and people can help with more specific questions.

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Redline Junkie
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Re: Switching to Standard Exhausts

#17 Post by Redline Junkie » Fri May 04, 2018 5:18 pm

I had a NOS set of those Cat pipes a few years and they are like bolting boat anchors on the bike again. If it were me, I would find a set of 31K Canadian pipes to give you the original look and get rid of those ones.
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JonW
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Re: Switching to Standard Exhausts

#18 Post by JonW » Fri May 04, 2018 9:22 pm

What Rob said!
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delboyphx
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Re: Switching to Standard Exhausts

#19 Post by delboyphx » Sat May 05, 2018 12:16 am

Also have a set of the original (non catalyst pipe) as well. These are showing some age and banged up a bit.
Preferring the boat anchors mainly due to the condition. Do agree they look a bit tame but objective is originality.

As further background I was at the Mecum motorcycle auction Jan 2018 (Las Vegas) and it was very noticeable the premium that a standard bike gets, not that I am about to sell but something that got me thinking about going down this path. 4 weeks time there is another auction same location, don't see any RZs listed so far but bikes get added right up to the auction. Perhaps some of you planning to attend, or selling.

Really want the 500 but getting kind of pricey.

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Re: Switching to Standard Exhausts

#20 Post by delboyphx » Sat May 05, 2018 12:32 am

Bikes most appropriate for this forum:
https://www.mecum.com/lots/LV0118-31500 ... aha-rz350/" onclick="window.open(this.href);return false;
with boat anchors
https://www.mecum.com/lots/LV0118-31502 ... uki-rg500/" onclick="window.open(this.href);return false;
https://www.mecum.com/lots/LV0118-31959 ... aha-rz500/" onclick="window.open(this.href);return false;

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Redline Junkie
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Re: Switching to Standard Exhausts

#21 Post by Redline Junkie » Sat May 05, 2018 7:05 am

I understand your goal and what I do is pack the oem parts away that I remove (air box, pipes, brakes, etc) when I put on aftermarket parts. That way I can ride the guts out of it and still have option to go back to stock look and performance. I have chambers, pods, jetting and triumph brakes done and it is a huge gain in performance and smile factor!! When I’m on a twisty back road I could care care less if it looks stock, I enjoy the roar of pipes and pods. Just my 2 cents
Last edited by Redline Junkie on Wed May 09, 2018 1:03 pm, edited 1 time in total.
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hondaror
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Re: Switching to Standard Exhausts

#22 Post by hondaror » Wed May 09, 2018 10:26 am

Redline Junkie wrote:I understand your goal and what I do is pack the oem parts away that I remove (air box, pipes, brakes, etc) when I put on aftermarket parts. That way I can ride the gusts out of it and still have option to go back to stock look and performance. I have chambers, pods, jetting and triumph brakes done and it is a huge gain in performance and smile factor!! When I’m on a twisty back road I could care care less if it looks stock, I enjoy the roar of pipes and pods. Just my 2 cents
I'm totally with you on this!!!
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delboyphx
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Re: Switching to Standard Exhausts

#23 Post by delboyphx » Sun May 13, 2018 10:45 pm

As it turned out the pilot and main jets the same as the factory recommended one, so that was not the issue. So back to thinking it is something specific with these exhausts. Their condition is like new but perhaps issues can develop in the catalytic converter when sitting this long, hard to know what is going and how these can be checked. I do have another set but as these are all banged up decided to put the tommey pipe back on and off course up and running great again.
So, for now will run this way.

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Re: Switching to Standard Exhausts

#24 Post by T.RexRacing » Mon May 14, 2018 10:43 am

You'll do your bike a favor by re-jetting for the Toomey pipes.
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Evans Ward
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Re: Switching to Standard Exhausts

#25 Post by Evans Ward » Mon May 14, 2018 10:51 am

If you are running the stock full airbox with stock linked carbs with Toomey's, see my signature below for my jetting specs to get you in the ballpark. Chuck "Supertune" Quenzler jetted my bike.

Can't imagine anyone using the heavy stock cat boat anchors exhausts unless in a static display for an original bike.
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evan_calgary
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Re: Switching to Standard Exhausts

#26 Post by evan_calgary » Mon May 14, 2018 8:00 pm

It is possible the cat pipes are badly plugged. It is also possible the stock jetting is too fat. Stock jetting in Calgary on my TZR it will not rev past 6k...

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Questo vecchio rz
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Re: Switching to Standard Exhausts

#27 Post by Questo vecchio rz » Mon Jun 04, 2018 11:08 am

If I read this right,
1.) your bike has 100% stock jetting? And you
2.) Removed your aftermarket expansion Chambers and reinstalled the OEM catalyzed exhuasts.

And your bike now feels sluggish, slower etc..

If that's the case...there's likley nothing wrong at all, You just restricted your motors potential buy a real and honest 11-13 h.p. as it's a U.S. spec emmisions bike. Your bike will run, as such with a noticable loss of grunt,actually a huge noticable loss, from what your used to.

You can run Chambers on a stock jetted RZ with no problem whatsoever at your elevation, and never worry. Re jetting would have been ideal, but not necessary.

If you were/are attempting to go back, to stock or if in fact the carbs are untouched..I'd leave it stock everywhere.
If I was interested in a stock machine, I'd want absolutely untouched OEM bike.

There's a possibility that your OEM pipes are partially clogged, due to catalyzed material breaking down after 30+ years? or oil/carbonsaturation if they were used for many miles..I'm thinking out loud, but I don't think you could clean them without causing damage to the existing material? But back to my 1st thoughts when reading, the stock pipes are very, very restrictive you just may be hitting that wall. It's something you absolutely would notice, as it's a massive decreases in performance everywhere in the powerband. Your going from high 50s in h.p down into the mid 40 h.p range..it would be a total buzz kill as far as performance.
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delboyphx
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Re: Switching to Standard Exhausts

#28 Post by delboyphx » Mon Jun 04, 2018 12:33 pm

Yes, you pretty much summed up precisely except the loss of performance is way more than normal, like above 6000 rpm you hit a wall. Standard exhausts now back in the box and useful for mainly for selling on with nice OEM pipes.

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