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How many miles have you had on the bike since the engine rebuild? Much highway riding?
Are you sure it’s not just condensation? Put a catch can on it to inspect the vapor residue.
Too much engine can sometimes be a culprit. Keep your bike upright and check the level.
How were the cylinders...
Agreed on the SS Helicoils. Although I am with you on using some type of anti-seize (I use a zinc-type compound, this one goes up to 750°F! https://www.amazon.com/dp/B004HMLCLI/ref=cm_sw_r_cp_api_oARaCbSAQQ2NH) I also find strangely contradictory that an anti-seize be applied to hardware that...
Though your tensioning bolt does look like OEM, that marking is on rubber that is fused onto a piece of flat metal, which over time can slip or knock itself off. I would not rely solely on that mark and there’s no harm in checking that the flat surface is facing in the correct direction which...
Trek97, one other note on the cam chain tensioner bolt that you had to twist around to show that the mark was facing outward... perhaps more important would be to make sure that the flat on that shaft is facing outward toward the hole where the bolt locks that part down. Hopefully, that’s not...
Trek97, one note about using stainless steel hardware on your engine (aluminum) is that galling can occur since SS is a harder metal than aluminum. Zinc-plated hardware may be the better option. Use Helicoils where you can and always try torquing to spec. Also try not to use that impact driver...
So here’s proof that this can be done - splitting the case while leaving the top-end on. I don’t like this method. It makes working with the engine a tad unwieldy. If you want to inspect/replace bearings or maybe the primary shaft drive/chain, con rods, can chain tensioner or gears, you probably...
Awesome! Congrats! Though, at the least I'd say put a front brake on that thing!
Get these bikes out on the road!
Things with my 400F are meh; things can always improve. Still getting some rides in. Because of the air pods and aftermarket exhaust, I had to upside my jets (88 Mains; 75 is...
The picture may be a bit misleading but yes, the exhaust does ride low. No off roadin’ with this bike and I’m careful over speed bumps and dips.
The exhaust is handmade from Outex (Japan). I like it a lot.
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More details on where I’m at with this build and how it’s come along since inception
IDK Numero Dos - 1975 Honda CB400F
https://r.tapatalk.com/shareLink?share_fid=13548&share_tid=159591&url=http%3A%2F%2Fforums%2Esohc4%2Enet%2Findex%2Ephp%3Ftopic%3D159591&share_type=t
Sent from my iPhone...
Thanks! Yeah, I was pretty fast on this one but as they say, haste makes waste... though I did check things over as I do. Newish cam chain, newish clutch discs, brand spankin’ new primary chain too. I’m thinking it could be that one of my shifting forks is bent :-/ We shall soon see.
Meanwhile...
Sorry I’ve not chimed in. I’ve been trying to fine tune the bike now after replacing the entire crankshaft assembly including the connector rods and all the bearings. So far so smooth on that aspect and most importantly, no more knocking!
New issue has arisen and that’s with 1st gear not...
Good go on the green Plastigauge. I’ve never used the red version...
Yeah, seems that my #4 rod journal had gone oval and spun the bearing, leaving wear marks both on the inside and outside. I wonder if the oil passage had been blocked or something. Strange.
I’m awaiting parts from DSS - I...
Re: 1975 CB400F Engine knocking
Ah! Thanks for those pics. I guess then it’s common that piece is worn down via can chain. I doubt that would be any source of knocking, however. It would just get chewed down as a result.
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Re: 1975 CB400F Engine knocking
With a micrometer I measured the journals, crankshaft mains and big end rods:
Main Bearing Journals
1 - 31.9777mm
2 - 31.9862mm
3 - 31.9862mm
4 - 31.9862mm
5 - 31.9887mm
Big End Rod Journals
1 - 31.9887mm
2 - 31.9887mm
3 - 31.9887mm
4 - 31.7830mm (up/down)...
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