Topic: RC eng. baffling Q?

[Don R]

 Did the baffle on the RC 4-1 originally have any fiberglass packing? 

[gschuld]

There were a bunch of variations of the RC 4/1 pipes over the 10ish year span.  But yes, all the street pipes that I recall had packing.  Most day raced sidewinders went gutted mega though.

George

[Don R]

 Thanks, that was my assumption. This bike was raced a bit so I feel fortunate that it even had a baffle. It was not bolted in, so I assume it was merely placed there to keep it from being lost. I'll give it a try with no packing before adding any, but I usually like the glass pack sound.

[NitroHunter]

My RC pipe's fiberglass baffling material burned out quickly, so I re-wrapped the core with industrial strength stainless steel Brillo pads and stuffed it back in. It ran better and I liked the sound more than when it was strait open. The MP's at the gate did too. 

[PeWe]

My RC 4-1, CB750 K7 model mounted on a K6 1979-1980 had fiberglass wool inside.

I robbed my speakers on some wool when time to refill, reduce the sound for street use. I refilled the speakers later on when I went by a house building site

[Tracksnblades1]

My life long buddies k6 RC sidewinder originally had packing. Installed briefly when new, then just a open megaphone. A Pringle’s potato chip cardboard can would calm all the megaphone music when he wanted to slip out of town undetected. Until it became overheated or dislodged by a blip of the throttle..😜

[Don R]

 All awesome stories. We used to run the hooker 4-1, after the mufflers burned out a steel V8 juice can found in beverage machines would make a nice baffle, you could tune the sound with bigger/smaller and more holes.
  Once I made a baffle liner from an old oil filter media after cutting a race filter open. After the ride there was no evidence of it ever being there. I always wondered if the muffler looked like a jet engine while I was riding.  (Edit, bike was unusually fast that day, maybe I'm on to something)
  I once made a baffle from a piece of metal I found in a box of stuff. I later realized it was the back from a K0 gauge. I probably should have kept that for future use.

[PeWe]

I used steel wool inside a 4-1 once. I noticed some lights behind bike when riding.

Flames out from the exhaust as an old Flash Gordon movie when the steel wool caught fire! The thin steel wool not good was my lesson.
Stock CB750 engine but loud.

[Don R]

 I had it running tonight and love the exhaust note at low rpm's with no packing. The clanging which I hope came from the loose clutch basket outer ring is alarming though. I'll be heartbroken if that's a rod bearing noise.

[Don R]

No fiberglass.  https://photos.app.goo.gl/LjHVLQrTKiAni86L6

[Alan F.]

That does sound GOOD.

[Don R]

 She's a little smokey and the idle is still high but I was excited to get it running. The PO wasn't sure why he stopped riding it in 87 so it was up in the air if it was broken or not. He couldn't even be sure it was the RC 836 engine until I described the porting and cam.

[dragracer]

Sounds healthy. What size carbs?

[Don R]

 Those are Mikuni 29 smoothbores, I really feel like I got the deal of the decade (at least for me) on these two bikes. I met the PO at a car show, he had been looking for someone that appreciated his 750 stuff. I am that guy.

[dragracer]

Those are Mikuni 29 smoothbores, I really feel like I got the deal of the decade (at least for me) on these two bikes. I met the PO at a car show, he had been looking for someone that appreciated his 750 stuff. I am that guy.

I never get that lucky to find a treasure trove. On the other hand I feel grateful to have the knowledge to build a few  solid  mid to low 10 second platforms without breaking the bank.

Good luck with your bikes. You've got good parts to work with as you move forward.

[Don R]

 Thanks. I hope to meet you guys at a track some day.
https://photos.app.goo.gl/5de4MPKXFDQYu5sy6

[PeWe]

That engine sounds healthy, not much rattle as a CB750 can sound

Videos seems to amplify rattles otherwise.

[Don R]

 That's true about hearing rattle noises. Other videos of it do catch noises. The clutch is only a small part of it, stays about the same with the lever pulled in. I'm thinking the baffle rattles a bit, I may give it a softener of some sort to eliminate the metal on metal contact. I also need to re-check the cam chain adjustment, I may have turned the motor when it was loose.

[Tracksnblades1]

if it's anything more than a rattle, it'll find its way out..😜

[Don R]

  Sometimes parts just mix up a little. L0L!

[Don R]

I never get that lucky to find a treasure trove. On the other hand I feel grateful to have the knowledge to build a few  solid  mid to low 10 second platforms without breaking the bank.

Good luck with your bikes. You've got good parts to work with as you move forward.
[/quote]

  Actually, you probably met this guy.  He was at Valdosta running his Hayabusa 2 or 3 years ago and said, in the lanes were all of these guys with 750 Hondas, I couldn't believe it! After he made his run, he followed somebody back to the pits, looked at the bikes and even left contact info, but said he never heard anything.
  Crazy Huh? He planned to bring the 750 stuff to the next race but didn't think he had room for it all in his trailer and still bring his own bike and tools. Then, things happened and he didn't make it back for a while.  I think he went to spectate this year because his bike did a backflip wheelie at Cordova and wasn't repaired yet.

[dragracer]

I never get that lucky to find a treasure trove. On the other hand I feel grateful to have the knowledge to build a few  solid  mid to low 10 second platforms without breaking the bank.

Good luck with your bikes. You've got good parts to work with as you move forward.

  Actually, you probably met this guy.  He was at Valdosta running his Hayabusa 2 or 3 years ago and said, in the lanes were all of these guys with 750 Hondas, I couldn't believe it! After he made his run, he followed somebody back to the pits, looked at the bikes and even left contact info, but said he never heard anything.
  Crazy Huh? He planned to bring the 750 stuff to the next race but didn't think he had room for it all in his trailer and still bring his own bike and tools. Then, things happened and he didn't make it back for a while.  I think he went to spectate this year because his bike did a backflip wheelie at Cordova and wasn't repaired yet.
[/quote]

Wow. Small world i suppose. I've had several people over the years approach me about parts but sometimes they don't follow up with contact information. MAybe Bill was the unlucky fella that passed on this deal. I'm glad you bought it all.

[Don R]

  This guy had some awesome stories about going to California and meeting Russ Collins, buying these parts direct at the shop.

[Don R]

 I grabbed a bag of fiberglass yesterday, have not tried packing it yet. I plan to run it as soon and as much as possible to see if it cleans up the exhaust any, it will be cold and I don't want wet packing.

[dragracer]

Who needs a baffle. Old school loud!!!!