[mpcycledesign]

I'm going to be doing the valve shims in another couple days and was just wondering what the pos/neg are for removing the cam silencing gears. How much noise can I expect? The article said it sounds like an idling Ducati clutch (which I can handle) - but once in motion - is it still loud or does the clanking go away...

 

[SubSailor]

Supposedly the reasons for removing the silencing gears is reliability for track use. It reduces the (slight) chance of failure by the silencing gears.
Also it reduces the cam drive train rotating mass by eliminating the weight of the silencing gears. And by doing so, it may add a (very) slight amount of HP to the engine.

Since the cam drive is by spur gears, the silencing gears (also known as split gears) eliminate lash in the gear train, and in turn quieting it down.

I still have mine installed, so I'll have to rely on those who have theirs removed to comment on the increased noise.

 

[kperham]

I met a guy at Road Atlanta track day that had his removed. His comment is that his bike sounds like a diesel VW. I didn't notice, but probably due to my earplugs and Yoshi slipons. He did say that they are strongly spring loaded and one of them embedded itself in his garage wall! So use caution! LOL

 

[mpcycledesign]

Thanks - I really appreciate the feedback!

 

[CBXJOHN]

From what I've seen on other Honda's (VFR), the cam gears are split, with a clockspring inside the wider (bearing) portion of the gear. This setup reduces gear backlash and noise. The only benefit as stated would be to reduce mass in the cam drive, a minimal benefit if any.

If you want to hear noise, listen to my CBX when cold. The cam sections (4) are keyed to the chain sprockets in the center, with oldham couplers. These couplers are basically a key-in-slot arrangement, which loosen with the contraction of a cool engine. Couple that up with 24 large shim-in-buckets singing the cold engine song, and you get the picture, Diesel orchestra. But it does sound cool. I love the cam whine of the RC, not quite as noisy as my 98 VFR 800 though.

John

 

[mpcycledesign]

OK - I did the shims yesterday and decided to leave the silencing gears in. Glad I did - when I got the engine buttoned up and fired it for the first time (this was a basket case) - it was plenty loud enough with the silencing gears in! What a lovely engine though - I was planning on fixing it up and selling it - I think I may have to keep this one... Besides being one beautiful bike - it is a bit dangerous... Just like my 636 - it's impossible to go slow...

 

[SubSailor]

I also have a Hayabusa, but the first time I rode my RC51 I told myself "this baby's gonna get me into a lot of trouble".
I just love hearing the engine through the rev range.

 

[BMW M 5]

oh...there is a lot of noise...belive me. Imagine ducati 916...with dry clutch and desmo valve lifters...It's sounds great...Rc 51 without this gear silencers sounds a double...

 

[jondog9]

Hmmmmm, tempting....

 

[screamin chief]

I thought I had read removal of those can cause damage. I may be wrong

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[madbuyer]

I thought I had read removal of those can cause damage. I may be wrong

Sent from Motorcycle.com Free App

+1....or at least reduced the reliability.

 

[gts455]

Read up, lots of debate on this subject.

http://www.speedzilla.com/forums/honda-rc51/50084-cam-gear-mod.html

http://www.speedzilla.com/forums/honda-rc51/13173-cam-silencing-gear-removal-mod.html

 

[SubSailor]

Well the Kent Cams set in my current engine have no quieting gears, so it will be interesting to hear those bad boys while once it gets to startup time.

 

[Waldo]

Mine should be in this or next week. Just need to get a degree wheel.

 

[gts455]

It's been awhile since i've looked into cams etc., how do the Kent cams compare to the HRC or Moriwaki stage 2 cams? Require a valvetrain? or are they more along the stage 1 route?

Trying to figure out, who makes a cam close to the HRC stage 2 spec.

 

[madbuyer]

Since the cam drive is by spur gears, the silencing gears (also known as split gears) eliminate lash in the gear train, and in turn quieting it down.

With your new cams, is this dictated by how the teeth are undercut or is there a spec. and procedure to set the lash?

 

[Polarbear]

you guys notice a big difference with the kent/moriwaki cams upgrade?

 

[Lycon86]

I took mine out and had it running next to a standard SP1, on Saturday just gone. It was hard to tell the difference in noise tbh. Power wise; bike had Durbahn carbon intake and GPR high cans with modified filters in a standard airbox. Also flapper valves removed/blocked. Power with anti-lash gears and these mods is 128hp and 77 torque.

 

[madbuyer]

I took mine out and had it running next to a standard SP1, on Saturday just gone. It was hard to tell the difference in noise tbh. Power wise; bike had Durbahn carbon intake and GPR high cans with modified filters in a standard airbox. Also flapper valves removed/blocked. Power with anti-lash gears and these mods is 128hp and 77 torque.

Somehow don't think most folks listen to your bike Lycon....she is dead sexy she is....

 

[Lycon86]

Somehow don't think most folks listen to your bike Lycon....she is dead sexy she is....

Haha. Cheers buddy. Tbh. If I said I didn't pull up to the only other sp1 in the pit garage, just to compare mechanical willies, I'd be lying. But I also wanted to see if mine was louder. As noise regs on British tracks is getting rediculous now. But his only just scraped through noise testing at 101.1 Db and mine sailed through at 98.3. He had akros on mind. Can't imagine how tho as my GPR cans don't have any baffles.