Engine casing cracks?

[Admangia]

I have a 2022 CT125 purchased in April and now with about 1300 miles of fun on it. However, looking at motor today and noticed what may be cracks or just poor quality casting below spark plug. I will need to bring to dealer but curious if anyone else has noticed this? ( see below)

 

[m in sc]

thats just a casting mark, not a crack, and is very normal. not poor quality, just the way it is and of zero concern.

 

[fmdualexhaust]

Agree. Mine looks exactly like that.

 

[Plotus]

Yes, of no concern at all...

 

[NMCoyote]

I wouldn't say there should be no concern, any flaw can become a crack depending on location and depth of casting flaw. That said, nothing you need to do other then monitor it, but if it dose crack you'll know. Just drive it hard while under warranty to expose any potential issues that you want them to be responsible for. Me, my only potential issue is with the left side instrument cluster, specify the turn signal switch is going to fail soon by the rate it's deteriorating. I've already made a claim as the dealer I bought from is about 200 miles away. They are going to send it to me once it shows up.

 

[oldskool]

I wouldn't say there should be no concern, any flaw can become a crack depending on location and depth of casting flaw. That said, nothing you need to do other then monitor it, but if it dose crack you'll know. Just drive it hard while under warranty to expose any potential issues that you want them to be responsible for. Me, my only potential issue is with the left side instrument cluster, specify the turn signal switch is going to fail soon by the rate it's deteriorating. I've already made a claim as the dealer I bought from is about 200 miles away. They are going to send it to me once it shows up.

Even if this particular flaw is not likely to fail it is not of no concern. They clearly had issues with that casting. Was it temperature, inclusions in the metal, both? Are there other areas that are unseen that are flawed. I would show it to the dealer. He will not do anything about it but if it fails two months past warranty it is documented that it was an issue that the dealer ignored. They are not giving these bikes away and that kind of subpar component should never have been let out the door.

 

[m in sc]

its not a flaw. thats how the casting is done. zero zero zero concern.

1st year grom cyl head, i have it here in the warehouse at work actually. same/similar casting marks, same with my 14 cb1100.

 

[oldskool]

its not a flaw. thats how the casting is done. zero zero zero concern.

1st year grom cyl head, i have it here in the warehouse at work actually. same/similar casting marks, same with my 14 cb1100.

What that visual FLAW indicates is substandard casting. Whether it leads to mechanical issues or not they did something wrong, metal temperature wrong, mold temperature wrong, injection pressure too low. That is not how casting is done if done correctly. Disappointing at the very least. My ,I understand that it's crap when I bought it, Ural has better craftsmanship in its cast parts than is shown on that 125.
The OPs DEFECT may be a cold shut. Caused by metal being injected from more than one point and the metal is too cool to fuse at the point it meets It is a flaw and results in a weaker casting. Where that one is may not cause grief, it is still very much a flaw. While I might expect such poor QC on a bike ordered from Alibaba I find it surprising it is common from Honda...?

 

[dmonkey]

Are we talking about the hairline mark traversing the cooling fin, or the deep dark groove from the casting that is slightly blackened with grime?

 

[m in sc]

every single bike i've ever owned (and ive owned many more than most) has had casting marks and 'flaws' on them. its there because... it doesn't matter. it's not a structural or cosmetic part. 2014 grom head below, mine. they have been making these same heads for 10+ years, and its not nor has ever been an issue, therefore not a flaw per-say, but a result of investment casting on a mass production scale. . I am sure they are well within the qc guidelines of honda motor corp. Unless you want to spend 700+ bucks on a 4v head setup with pretty casting lines (and they do have them) this is what you get. even the top of the line stuff has 'flaws'. look at the link, and the pic of the head. to the left of the exhaust port. right ere on the boss is the 'flaw'. I had this setup. Unless you're willing to get a hand made sandcase part, this is pretty normal. https://www.steadygarage.com/collec...d-honda-grom-125?_pos=97&_fid=844fe260d&_ss=c

 

[NMCoyote]

The internal pressures generated by this little motor would hardly case any concern of cracking at the flaw, and it is a flaw, but an acceptable flaw due to the location and low strength needed to contain the 9HP this beast puts out? That said it' more likely to crack due to vibration/ or impact with something

 

[m in sc]

you guys are picking this apart like its a new MV agusta or something . lol. when i was doing QC for Dellner Couplers, we would get castings of coupler heads we had to check, they had marks/flashing/inclusions way bigger than these that had to pass railroad industry standards (iris). they are allowable variations, and are and were not ever described as 'flaws'. If you have ever ridden a commuter passenger train in the us, or flown thru the atlanta airport, you've been pulled around by one of these couplers with 'flaws'. ever heard of a coupler casting breaking? didn't think so.

 

[oldskool]

Sorry I worked at a machine shop many years ago that made aircraft parts, no minor defects accepted, period. My bikes don't have these casting flaws and I wouldn't leave the dealer with one if I knew such flaws were present. I don't accept any orange peel in a paint job either but I guess that's just me. My wife gets impatient with me at times when working on home projects..." your not sending a rocket to the moon it doesn't need to be perfect"

 

[m in sc]

look harder at your bike, the castings aren't 'perfect'. the past 24 yrs, for me, and still are, being spent in engineering, manufacturing, qc and with a lot of hands on prototyping.. which included machining (some of cast parts). As long as there's no internal voids, and the min thickness is there with consistency of material composition, the complaint here is on an aesthetics issue alone, not a functional one. But to each their own. and if anyone thinks its a flaw worth action, reach out to Honda, see if you get a new motor out of it.

 

[NMCoyote]

Sorry I worked at a machine shop many years ago that made aircraft parts, no minor defects accepted, period. My bikes don't have these casting flaws and I wouldn't leave the dealer with one if I knew such flaws were present. I don't accept any orange peel in a paint job either but I guess that's just me. My wife gets impatient with me at times when working on home projects..." your not sending a rocket to the moon it doesn't need to be perfect"

yeah, it does need to be perfect or why do it at all! That's my philosophy.

 

[AZ7000']

No, mines bigger!

 

[burnpile]

Remember on the ct 110 or 90,s the hole in the head? a casting defect on all bikes that doesn't matter. it wasn't actually a hole but did look like one.

 

[AZ7000']

Remember on the ct 110 or 90,s the hole in the head? a casting defect on all bikes that doesn't matter. it wasn't actually a hole but did look like one.

 

[dmonkey]

The "speed hole" is good for another 1-2 mph! My CM91 has it as well.


The C70 does not. Very slow



If whatever crack you see remains the same and isn't causing any issue then I wouldn't bother with it unless you're going for a show bike, enjoy riding the motorcycle. If it grows then reach out to Honda customer support, replace it, go aftermarket, or get it welded.

Sometimes you have to remind yourself these things aren't going to space, they're just imperfect little motorbikes that take on wear and tear with use. There are countless motorcycles out there racking up miles with chipped and missing cooling fins.

Here's an assortment of functional issues, things to actually worry about, and often worth repairing when parts aren't available or cost an arm and a leg:
1919 Harley-Davidson model J cannonball motorcycle with many chipped off jug fins and replacements welded back on. Cast iron.


1948 Harley-Davidson Panhead, Sean Jackson's 2023 Biltwell People's Champ motorcycle, undergoing repair to the original cases. Aluminum.



Harley-Davidson JD cannonball motorcycle repair to a cracked jug at the valve pocket. Cast iron.

 

[Little_Thumper_Boy]

Gentlemen/Admangia, not a flaw, not a defect. Looked on my own CT in the exact same spot and it also bears an inconsistency compared to the surrounding surfaces. Mine's a rough, lumpy joint line with the same diagonal-direction feature and in the same location, but with small rises and recesses instead of a constant recess. It's most likely either a joint from a mold insert/seam, or some parting line where the wax (plastic) or sacrificial molding matrix butts to the adjacent one there. Not to worry; the thickness of the aluminum in the region is huge compared to the depth of that recess. If you were to measure the recess ("crack") it would probably be on the order of 1/2mm IME.