Cruzinimage pistons and rings

[Bryanj]

Genuine Honda were made by Art

[Oddjob]

I'm not sure if the rings Cruzinimage were using a few years ago are the same as what they are using now.. The image of the new rings fitted down the bore prior to fitting showed them stamped with the oversize number not an R.

Saying that, aren't Honda ones stamped with a T, meaning Top?. Like an orientation marking not a manufacturers marking?

As for no reports of problems with the pistons/rings fitted by members, would there really be any yet? They don't seize or do anything that would make you suspect them, the rings just wear fast according to what I'm reading, we don't really do THAT many miles on our bikes these days so the problem may not show for a few years, the first thing would be a drop in performance as the compression went down, as the bikes recently had a rebore etc that last thing you'd suspect would be that, you'd go through everything else. After some more miles had passed maybe they'd start to allow oil to be burned, so a little blue smoke maybe, we'd suspect valve stems seals etc before we'd suspect the rings.

I was very hesitant to promote fitting Cruzinimage in the past, like a lot of ex mechanics we don't like aftermarket parts, they tend not to fit well and be of poor quality, however after reading so many members who had fitted them or had them fitted by others on their behalf I came to the conclusion that they must be ok. I'm not saying now that they are not, I'm just saying reports out on the web are saying they might not be as good as we first thought, it might also explain the defensive attitude that Cruzinimage exhibits to criticism, after a few complaints you tend to get very defensive.

I'll not say where I'm reading this yet Ash, let's see if there may be some truth in it first, I have reasons for not linking it in, most notably because some members will get really upset over some of the other posts and I don't want to do that.

[Nurse Julie]

Ah yes, I've recently read Mike Nixons Cycle Project myths and tips on the CB350. He was saying it was common knowledge the Cruzinimage big bore kits for the CB350/4 had soft piston rings, leading to probably wearing out the rings resulting in oil burning within a few hundred miles of fitting. So yes, that's a known problem. We never fit big bore kits to our own engines or any customers.

[Bryanj]

The reports i have seen on the US site were all 350 four which have the smallest bore size of all the fours and have the tightest tolerance piston to bore.
Most, if not all the reports have eventually concluded that the machinists doing the work did not work to Honda specs because in their opinion it was too tight and would sieze, a fact disproved by a later, understanding, machinist.
Now i have never even seen a 350 four in person, let alone worked on one but the 400 is bad enough and requires a smaller boring bar than i have making me wonder if these US machinists were simly honing out the metal and not boring properly.

Just my own thoughts with no certain proof

[Sesman]

I'll not say where I'm reading this yet Ash, let's see if there may be some truth in it first, I have reasons for not linking it in, most notably because some members will get really upset over some of the other posts and I don't want to do

Send the link, I need a little stimulus….

[Sesman]

Oh, I love this Nixon bloke. I can see what you mean now, Ken.

[taysidedragon]

I fitted Cruzinimage pistons and rings to my 400four , it's done well over 1000 miles since rebuild and absolutely no problems whatsoever. 

I wonder if there are any fakes out there. Any successful, popular brand of anything these days gets copied by Chinese/Far East rip off merchants.

[DomP]

Yes to be honest I'm not at risk of putting mega mileage on my 550 so I won't lose any sleep over it

[Oddjob]

Ah yes, I've recently read Mike Nixons Cycle Project myths and tips on the CB350. He was saying it was common knowledge the Cruzinimage big bore kits for the CB350/4 had soft piston rings, leading to probably wearing out the rings resulting in oil burning within a few hundred miles of fitting. So yes, that's a known problem. We never fit big bore kits to our own engines or any customers.

You would imagine though Julie that Cruzinimage sourced the rings from the same place they source their other rings from IF they don't make them themselves. The rings in question were labelled 3.00 so that makes them 50mm x 50mm, with the 400 being 51mm x 50mm, that makes you worry about the 400 rings.

IF I had a 350 that needed a bore I'd be thinking of either fitting a set of 400 barrels (if that's possible) or if it's not then fitting the liners out of a 400 set of barrels into the 350 barrels, like I'm doing with the 550 liners into a set of 500 barrels. And yes I know the 550 barrels already fit onto 500 cases (except early cases that is) but I have a set of 500 barrels with good fins (but really rusty liners) and a set of 550 barrels with loads of broken fins but really good liners. Saves binning them both.

[Oddjob]

Oh, I love this Nixon bloke. I can see what you mean now, Ken.

Yeah, some nasty comments about the SOHC.net site and certain members on there. Also not a big fan of Mark Paris and his 750 book.

You see the comments about NOT honing bores except after a rebore and even then only with specialised equipment? Interesting.

I've actually been talking to Mike regarding the special tool for adjusting the clutch adjuster on the 500-4, never knew there was one but I've got the part number now and Roo is sourcing me one from the USA whilst he's over there.

[Nurse Julie]

Ah yes, I've recently read Mike Nixons Cycle Project myths and tips on the CB350. He was saying it was common knowledge the Cruzinimage big bore kits for the CB350/4 had soft piston rings, leading to probably wearing out the rings resulting in oil burning within a few hundred miles of fitting. So yes, that's a known problem. We never fit big bore kits to our own engines or any customers.

You would imagine though Julie that Cruzinimage sourced the rings from the same place they source their other rings from IF they don't make them themselves. The rings in question were labelled 3.00 so that makes them 50mm x 50mm, with the 400 being 51mm x 50mm, that makes you worry about the 400 rings.

I don't think the Cruzinimage 3.0 over big bore kits use the same piston rings as the 400/4 on their 0.25/.50/. 75 over. They have different marking on them and I've read the 350 big bore rings have a different profile or shape on the oil rings. But, as always, it's owners choice what they use.
But, stock of OEM 400/4 pistons / rings etc are very limited these days. Even Yamiya sell the Cruzinimage kits and they aren't know for selling dodgy products.

[philward]

I've got big bore kits on my standard 750k2 and CR750 Rep. About 4000 miles on K2 and 300 miles on the CR - no issues at all

[Sesman]

Offtopic, but I note Mike mentions not having to live with brake squeal, but I don’t see an article on how to cure it. Did I miss it?

[Nurse Julie]

Offtopic, but I note Mike mentions not having to live with brake squeal, but I don’t see an article on how to cure it. Did I miss it?

https://www.motorcycleproject.com/text/brake_ills.html

[Sesman]

Thanks, Julie. I’ve just noticed the ‘more tech articles’. Need to go to spec savers (other opticians are available).🫣👍