What was the difference, if it was just the lift it might fit and still work fine
Honda CBR400RR - unusual noise, what do you think it is?
- Thread starter West Cork Paul
- Start date
I’m assuming it’s got a slightly different cam profile between NC23 and NC29What was the difference, if it was just the lift it might fit and still work fine
. There must be some difference or else they’d have the same part number I would have thought. Yep it’s the 2nd, spring loaded, gear wheel that’s missing a chunk. I know think, having seen some fragments down in the shaft the gear wheels sit in, that perhaps just one tooth sheared off but as the teeth on the other wheel have to then deal with a gap they go slightly out of step and start smacking into the next tooth as they re-engage so that tooth experiences excessive force until it too shears off leaving a bigger gap and a worse problem for the next tooth after the gap and so on etc etc.
I’ll upload a photo of the fragments if I can get it on my phone
A "prize", I'm thinking it's one of those invisible one's but I don't care I'll take it whatever.Well, @Hughdg wins the prize. The noise is indeed ‘cammy’. I lifted the head today. I wish I’d done that first before fixing all the ‘easy’ stuff to get it back on the road for him.
View attachment 124691
Can anyone spot what’s missing?
Feck knows where that’s gone for it’s a fecking big chunk of metal but the only place it can go is down into the crank. Yet there were no metal shavings stuck to the sump plug or bits of brassy bearing in the oil when I drained it so I reckon it’s one large lump sitting at the bottom of the crank
Trophies are nowt to do with me, I never got oneffs don't ask for a trophy, it comes a year late
maybe @WAYNE will send his over.
I’ve been asking some questions of some people that know a lot about Hondas. Apparently the broken gear wheel, and its intact sibling on the exhaust cam, can simply be removed and junked and the cam reinstalled. They’re just there to reduce noise from the cam train. Thus, it’s not necessary to buy a new camshaft.
Now, what to do about the fragments.
Now, what to do about the fragments
.
Magnet fishing?I’ve been asking some questions of some people that know a lot about Hondas. Apparently the broken gear wheel, and its intact sibling on the exhaust cam, can simply be removed and junked and the cam reinstalled. They’re just there to reduce noise from the cam train. Thus, it’s not necessary to buy a new camshaft.
Now, what to do about the fragments
Ger
Well-known member
I guess you could . . The gear is spring loaded to just take up the lash .....the problem is getting hold of the broken parts ..... If you could you could match them up to the broken sprocket jigsaw wise to see if you have got all the bits ....I’ve been asking some questions of some people that know a lot about Hondas. Apparently the broken gear wheel, and its intact sibling on the exhaust cam, can simply be removed and junked and the cam reinstalled. They’re just there to reduce noise from the cam train. Thus, it’s not necessary to buy a new camshaft.
Now, what to do about the fragments
Absolutely Dave, that’s what I’m going to suggest to him today. I will drain the oil (again) remove the sump pan and fish out any bits in there. Looking at the parts diagrams it appears any debris would have dropped down the gear train channel, bypassed the big ends, and ended up at the bottom of the sump pan. On the basis the bike was running ok and from the unusual ‘cammy’ noise, it will run again.
I will be warning him however it could be a ticking time bomb
Ger
Well-known member
I'd make sure the shitter owner knows the full extent of it .....and it's basically possible it could go bang.....a nice gear train which wouldn't appreciate bits of gear lobbed into it @16000 Rpm ....thinking about it ....I don't think I'd offer the "fix" tbh ....
None of my business Paul .... etc ..
None of my business Paul .... etc ..
5 litres of unleaded.. Don't put it in the tank just pour it all over the scrapper and walk awayI’ve been asking some questions of some people that know a lot about Hondas. Apparently the broken gear wheel, and its intact sibling on the exhaust cam, can simply be removed and junked and the cam reinstalled. They’re just there to reduce noise from the cam train. Thus, it’s not necessary to buy a new camshaft.
Now, what to do about the fragments
Good idea - except he doesn’t have insurance….. or a valid licence5 litres of unleaded.. Don't put it in the tank just pour it all over the scrapper and walk away
…. or valid road tax. I tell you it’s the Wild West out here.
And that's before we even consider what they feed their cattle.Good idea - except he doesn’t have insurance….. or a valid licence
Fecking cowboys!
It was suggested by someone outside this community I could just remove the silencer wheel and refit the camshaft. Unfortunately the gear wheels on this model aren’t simply bolted together so there’s some pins need to have heads ground off and then be drifted out. However, before I do that I need to answer the question how do I get the silencer wheel off the cam it’s separated from the main gear wheel? Both the main gear wheel and its silencer wheel must be fixed to the camshaft somehow otherwise they’d spin rather than rotate the cam.
Has anyone any ideas?
Has anyone any ideas?
Are those pins that you propose to grind out , the very thing holding the drive gear to the camshaft
As well, an interference fit on the gears / camshaft
Paul, the broken sprung lash gear is pinned to cam gear which in turn has been sweated on the camshaft, I wouldn't bother feckin about, found this......
HONDA CBR400 NC29 EARLY (1990-1993 RRL-RRN )EXHAUST CAMSHAFT CAM | eBay UK
Used exhaust camshaft taken from a 1991 Honda CBR400 NC29. Good condition as shown in the pictures.
www.ebay.co.uk
I worked out how to do it. The 2 gear wheels aren’t fixed to the camshaft but fixed to a mount which is fixed to the camshaft. They’re held onto the mount by the pins. Remove the pins and they both come off
. That’s the theory anyway.
Thanks BobPaul, the broken sprung lash gear is pinned to cam gear which in turn has been sweated on the camshaft, I wouldn't bother feckin about, found this......
HONDA CBR400 NC29 EARLY (1990-1993 RRL-RRN )EXHAUST CAMSHAFT CAM | eBay UK
Used exhaust camshaft taken from a 1991 Honda CBR400 NC29. Good condition as shown in the pictures.www.ebay.co.uk
Thats the exhaust cam though, I need the inlet cam, which I can’t find anywhere I’d much rather replace the cam than butcher it, not that it’s not butchered already.
Sorry cocker, copied wrong link...................
Paul if you have any issues with posting to Eire, let me know and I get it and send it on
Thank you for that. I searched under a whole load of different search terms and that never came up
Were you searching on safariThank you for that. I searched under a whole load of different search terms and that never came up
asking for a friend 
Google actuallyWere you searching on safari
Why? Thankfully the exhaust studs for once just undid and I didn’t have a humongous fight with them.
BTW, I don’t have to butcher the camshaft now because @BobTheBounder helped me out. Thank you Bob.
Just got to get it over here now.
Bob. Just got to get it over here now.
Whatever Paul is offering you Bob, I'll double it!BTW, I don’t have to butcher the camshaft now because @BobTheBounder helped me out. Thank you
Just got to get it over here now.