Honda CB250N Superdream. Head, cylinders & Pistons removal. It's a long one!

Slowly slowly catchee monkey and all that. Although this is still heavily edited, I didn't want to cut out too much as I hope that my endeavours (both good and bad) might be useful for anyone else doing this with a superdream.

[@sidwainhouse]

There will be an engineering company near you that could do a rebore and supply pistons to fit. Don't rush out and buy anything, if you get the company that does the rebore to supply the pistons you'll save yourself a bit of hassle. You could also get them to skim the head, inspect/renew valve seats/stems, vapour blast etc. I'd do a complete strip and get all the cases done, inspect/replace the big ends etc whilst the engine is in bits. Don't bother paying out any money for frame coating etc just yet, wait until you are 100% that the engine is good before splashing out the cash. This is why we do dry builds. Good job so far Nat. 👍👍👍

[@NatsNackersYard]

Best advice this project mate. Must appreciated.

[@stevesanelli90]

Hi Nat, great job getting the engine apart! You do what you can with the tools you have. The cylinder bores can be honed. The pistons are fine but the rings need to be replaced. The rust inside is a concern. There’s been water in the oil so that could be a water pump issue or a missing dowel & seal on the head. I only saw 3 dowels, unless the other is stuck on the cases. The gearbox is the next big thing. Tip: ziplock bags & a marker are your closest friends. Take lots of photos as you go. Don’t leave anything to memory. The workshop manual is printed to get dirty. This will be a fantastic project!

[@NatsNackersYard]

Ziplock are a great call buddy

[@RyansGarageUK]

Glad you see your engine didn't have badly corroded headbolts where they are exposed to the elements. Clearly the rings wouldn't have been doing anything like that. 👍🏻

[@NatsNackersYard]

Some bits are OK on this, some are awful. luck of the draw I think.

[@H-M-78]

I'm impressed you have motivation working with a problem engine like this.

[@NatsNackersYard]

diligence and dumb stupidity are often confused.....

[@ianhorabin9763]

Full tear dwn, gearbox the lot,then rebore,new pistons & rings..don't just rebuild the top agen..it,ll cause more grief.. better having peace of mind by checking the lot..Ian👍👍

[@NatsNackersYard]

Good advice as ever mate

[@johnneild3914]

Well done nat id recommend rebore and new pistons cheers and cold beers John

[@NatsNackersYard]

Sold, sold and sold!

[@fredbailey2076]

Now if you had loosend them off in the frame you wouldn't be struggling on the floor with the additional advantage of possible moving the top end, making it easier to remove

[@NatsNackersYard]

Now you tell me!

[@karlvanboxel561]

Lol head gaskets fine ! Pull the other one Nat 😂

[@NatsNackersYard]

well they were in one piece!

[@timparker9235]

well done on not having a sheared bolt like Ryan and Rye - did you put any penetrating fluid down the one bolt that is open to the elements at the front of the head? I wonder if the cylinder that had poor compression, had no (or a loose) spark plug allowing water ingress perhaps? I'd be thinking a rebore looking at the state of that bore - good progress though Nat !

[@NatsNackersYard]

Thanks mate. just time and care on the bolts seemed to work mate.

[@karlvanboxel561]

Try cruisin image for pistons rings pins n clips unreal prices they have stuff for older bikes

[@NatsNackersYard]

thanks mate. I will have a look

[@fredbailey2076]

Ps thar rotor is going to be a bitch too

[@luddite6239]

Only if Nat remembers to call it a rotor and not a stator!

[@fredbailey2076]

@@luddite6239 rotors rotate I stators stay

[@luddite6239]

@@fredbailey2076 You know that, and I know that...🙄

[@derekdingwall]

You've got quite a project on your hands there Nat👍

[@NatsNackersYard]

I did not know that!

[@ZafiraSteve]

Second

[@NatsNackersYard]

lol

[@wibblywobblyidiotvision]

As Fred says, order of operations is a bit out, and not being your friend. That said, well done getting it apart without fucking it up. I wouldn't piss about with a hone, that cylinder looks pretty mangy. Rebore and upsize the pistons (for a handy power boost hahaha). A +0.5 piston kit is peanuts.

[@fredbailey2076]

Ide investigate a set of 400or 450 cylinders can't be any more than a 250

[@NatsNackersYard]

right as usual mate