750 K0 - K1 Exhaust Baffles

[philward]

I'm thinking of fitting KO - K1 baffles -
https://www.ebay.co.uk/itm/New-Genuine-Honda-Exhaust-Muffler-Baffles-69-71-CB750-K-K0-Pipes-Diffusers-R60/361711454839?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649
to the CR750 race exhausts on my road going CR 750 Rep to quiet them down (planning a few months ahead).
The CR race exhaust outlet diameter is the same as my K2 standard exhausts - the smaller K2 little black baffles fit straight in the CR outlet (I won't call it a silencer because its straight through!). I'd obviously have to make modifications to the CR exhaust to secure them
Question is:-
Are the KO - K1 exhaust outlet diameter the same as the K2? Don't want to buy a set if they are a different size.
Thanks

[AshimotoK0]

Not sure but if anyone knows off the top of their head Phil but if not, I could always measure a HM300 for you tonight.

[philward]

Thanks Ash

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[UK Pete]

I have 3 nos ones for sale but am in Tenerife at the moment


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[philward]

I have 3 nos ones for sale but am in Tenerife at the moment


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Pete, when I find out if they will fit, I'll pm you - no rush as it's not one of my priority jobs

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[AshimotoK0]

Not so sure this information is enough Phil ...   I removed the fixing bolt from the HM300 (genuine Honda) but the baffle wouldn't budge to measure it properly. They are new so I  didn't want to force anything. Anyway here are the external measurements I marked up a pic of a baffle on the internet)

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[steff750]

  hi  yes the outside diameters are the same ,but the inside of the k0-k1 baffles are a lot longer than the k2 as the k2 really are end caps with a smaller outlet ,so fitting k2 baffles would tone it down a bit but very restricted outlet power wise as you are aware the open megas and k0-k1 exhausts are what really make these bikes sing lol
i have fitted k0 baffles to k2 exhaust as they had rotted their internal baffles, there is no support inside the k2 baffles for them to fit securely,so the only support you will have will be the securing bolt at the back so not the ideal answer .and if you cut the ends off the k0-k1 baffles you would back to where you started with the open megas namely really loud pipes which i love lol

[philward]

Thanks Ash - looks like they're the same dimensions
Steph - was looking to use them modified with a perforated tube extending from end of baffle that would meet the downpipe internally where they join the 'silencer' - hence providing internal support. The bike has got to be useable (although I will probably only use it to ride to local bike events as it will be that uncomfortable!) and based on the youtube video's of CR750 Reps with the race rep exhaust I have, without some form of baffles, it will break the neighbours windows!
At this stage, I'm just thinking of ways of quieting them down

[Trigger]

You can buy DB killers in different sizes which just bolt in 

[philward]

The beauty of using the standard baffles is they slot in but the flanges 'but up' against the end of the silencer (stopping the baffles falling into the silencer and aiding the making of rear securing bolting) - the DB Killers (53mm) would need a lot more modding of the race exhausts - and at 900 squid, I don't want to butcher them too much

[K2-K6]

If it sounds anything like this

500 mv 3 cylinder at 2010 manx gp hillberry: http://youtu.be/f410HRvyOjw

Then I can see you'd have a problem with the neighbours.