Project Honda CB250RSD Project

What I've done today? Well, if you really want to know..
Some weeks ago I've bought this Honda CB250 RSD


just because I wanted a small Honda single. Could get or afford 500, this came very cheap. Replaced the stator by a CX500 spare I had on the shelf, cleaned the carb and it started on the first try. So let's take it apart and inspect all the bits. All old bikes in this price range ( < 200 Euro) are always a surprise package.

Today I finished unpacking it



It may look as if I've discarded all the bits not worth keeping but not really. The current list of parts needed runs to something like 400 Euro's for tires, drive+cam chain, etc,etc.

Only part I still haven't found is an inlet manifold (official name : carburettor isolator). The one that came with the bike is home made. Should have one lying around (Honda PN 16211-471-000) or know where I can get one at a reasonable price please let me know. Doesn't matter if it has the usual cracks in the rubber, there are fixes for that.

cheers, Frans

 

Seems I've mismanaged the pictures and can no longer edit the post, but these were meant to be there :

starting point:



and after today :



next comes cleaning and inspecting all...

 

How about that ! This has been upgraded to a project by the moderators !

I didn't enter it as a project because that would imply an obligation to report on it, have work schedules, pictures and all that. Well, OK, I will let you know what is happening but it will be slow....... Target is not a showroom bike, just to get it back on the road and ride it but not on tires 23 Years old. Hope I like it, the little CB250 nighthawk is fun but a few extra horses would be nice .

@my67xr : thanks, but that won't fit, too small. Rumour has it that one from a CJ250 can be made to fit but I cannot find that either.

 

To my surprise there is a 1.85 rim on the (cb250 RSD) rear and Honda wants me to put a 4.10-18 tire on that ? The rim is the same as the one on the front ??

Can someone who has a CB250 RSD please check if this is normal please?

As affordable tires were a bit of an issue I've followed the Metzeler book and ordered ME22's, 3.00-18 front and 3.50-18 rear. Metzeler says a 3.50 is the widest tire I can use on a 1.85 x 18 inch rim. Rolling circumference of a 3.50 - 18 is about the same as for a 4.10-18. Nice and cheap (as tires go) and good to 150 kph which should be enough. Getting the tubes for them is proving to be a nuisance, lots of people will sell tires but not the tubes to match. Don't even ask for a rim tape! Found that the local moped trade can supply, they're used to tube type tires.

 

Minor update and issue ! I've cleaned up the frame, turns out some PO powder coated it and little rust. Even the swingarm and steering bearings were in good condition and can stay put.

Parts are coming in from various parts of Europe, that goes well except for the inlet manifold. I finally found one in an obscure corner of Ebay Germany and ordered it. The part that arrived looked pretty good




but on closer examination seems to be one for a XL500, it is marked "435" (just visible in the picture) which is the Honda model code for an XL500. CB250 RS should be 471. Anyone here ever used this on a 250? I know some folks have fitted 500 engines instead of the 250 and maybe the guy who dismantled the bike and sold me the part never recognised it...

Now looking at what to do with rusty spokes, tatty wheel hubs and pitted rims . Maybe just clean them, get it on the road first? At least I got the old tires off.

Already spending on parts is twice what the bike cost me, and still counting ...

 

Yeah, painting is an option, but the hubs should be black, spokes chromed and the rims are now pitted alloy with a few bits of clear coating. Just how did you degrease or clean the wheels?

Love the picture of the 100 though, thanks! Many moons ago I started my motorcycle career - limited as it is - on a red A100 which served me well for several years and took me to many places in W-Europe. Only one rebore, plus many sparkplugs and headgaskets for decokes, apart from that never a problem. Looking back that must have been one really tough engine, usually running flat out for some 50K km's.

(now the friend I sold it to might think differently - a fork spring broke, he thought the bumping was normal and cracked the frame (!))

 

Hi Murdo,

I've already had a bit of a go with the high pressure hose and a degreaser, main result is yes, cleaner but most of all the corrosion is now more visible. Maybe I should start saving for new spokes, never spoked a wheel before but there's a first time for everything. That'll have to wait, cost is already too high now, let it run first then maybe next year. Taking a holiday anyway, this is developing into a winter project.

BTW, cannot access the 100's story as a non-member and I'm already active on too many bike forums so won't join. But it is nice to see it restored. My A100 was a rarity even at the time here and I've never seen one since apart from a nice (and expensive) one in the UK.

thx, Frans

 

Thanks Allan,

for checking. Normal then, but all tire manufacturers seem to think that 3.50 is the absolute max for an 1.85 rim....
Talked to a knowlegdeable ex Honda employee about that - seems he even did the mçycle tire courses - and he said that for volume buyers like Honda they often suddenly found that an execption was technically possible

He also said that with a 3.50x18 (which is what I've got for it now) the bike would probably handle better. Oh well, we'll find out once it gets on the road. Maybe it looks a bit meager from the rear but now corners well over 100 Mph

 

Hi Murdo,

thanks and yes, I did see them, should fit but the small rings Honda uses are absent. Don't know if that is really a problem. The price seems reasonable f.o.b., but by the time I would get them they'd cost me something like 140-150 US dollars and that is a bit too much, at least for now. Looks like the project will be split, phase one is getting it back on the road and running well. If there are no major disasters like unfixable fork seal leaks or camshafts dropping out I might consider luxuries like new paint and chrome.

As expected this is a money pit. To add insult someone here is now advertising a nice looking exactly same bike, running. High bid after a week is what I've already paid for parts so far and still need brakes stuff and other minor bits. Well I did say I needed a bike to work on didn't I? Got what I wished for !

 

Yes, still here, but as said it would be slowwwwwww..... But nice to be back and see people here doing things like nickel plating their carb jets. Great, no idea why but it does make me feel at home where this type of activities are perfectly normal and appreciated

After a long bit of a holiday and other stuff to keep me busy I've returned to the garage and the latest victim, the CB250RS. The frame is now clean, headstock, swingarm in place looking good. Cleaned up the rear wheel and added a little bit of black spray paint to the hub just for looks. Added a Metzeler by hand. Now I hadn't done that since the last Suzuki GT250 bought new and managed to pinch the tube. Bought new tube and got it right 2nd time around. So much for old experience.

Anyway, there is a visible result now :



Now if only I could remember where I put the pedals .....

I'll be back!

 

For the record, an update. Things are looking up :



The bike now has wheels again - clean and bit of a polish , new tires in place. Fork legs flushed once and new 10W oil, seems very soft but I'll know once I get it on the road. For now all the electrical bits are being checked, cleaned and fitted in the (factory) correct places, the cabling was in a very poor state and this is a good time to fix it properly. Thirty+ years of muck don't improve reliabilty. (of course everything I do greatly improves it ). It is starting to look good from a distance really.
There seems to be a curse on getting parts for this bike. First the wrong carb isolator from Germany - money back after proposing a formal complaint to ebay - and now a parcel with the rear grabrails seems to have disappeared in transit, again from Germany.

Anyway, these are the easy bits, the heap of parts is getting smaller as they go back on the bike. At the bottom af this heap is a little dirty old black engine, slowly becoming visible. It can run, that much is known .....

 

yes,yes, this is still an ongoing project and you'll have to admit there is visible progress, I mean look at it, as first encountered (cheap opportunities of the Nth-hand kind) :




and current looks



all the dust has now been wiped off. The engine has been located (hiding next to the fridge behind the front wheel) and will now finally get some attention. Bit of a worry that, but it did at least run idle before I took it out. Still have to find the money for a new camchain and other little bits as needed, but on the upside : a kind soul spontaneously offered me his spare carb isolator for all of 5 Euro's - yes I'll have it please!!! - and a set of reasonable rear grab rails came from Germany, blinkers included. The paint on the front mudguard as removedby a previous owner (by black using a leaky brake master) has been replaced by black spray, shiny arrow just for looks and an extra clear layer. Looks nice, hope it'll stay put next to the hot exhaust. A fresh brake master is on it's way here and the caliperhas been replaced by a double piston one from a GL500 which fits and has about the same total piston surface area as the original so should be OK.
Lot of stuff from the CX500 series seems to fit on this bike which is handy as I've got lots of that lying around. Even a CX500 choke cable seems to fit.

Also noticed that there is no "CB250RS" sticker on the side covers. Strange, as Honda sold them only as a set with the stripes which are present. But if they're available at all original Honda decals are rather expensive, will have to ask around locally if they can made up.

So, once the engine is (say) refurbished it could still be a lousy runner but at least there will be shiny bits!

to be continued... sometime in the future...

 

Don't worry, while it's not completely unthinkable I'll turn up in Canberra some day (relative there) it'll be without this bike then, don't want to hurt anybodies feelings about the woodwork Anyway, it wouldn't fit in the overhead bin of the cattle class aircraft seats I normally use.

But, should I ever reach Canberra, we can always have a serious discussion about it of course