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Life at 20,000rpm. AU restore.

13309 Views 51 Replies 10 Participants Last post by  kula
Hey all

I managed to score a 1991 CBR250RR. MC22-L.

It's been there 7 years, and it hasn't moved in that time.

It's a jap import Honda CBR250RR. 1991. MC22.

I was gonna rent a ute, but realised an uncle in law has one that gets bugger all useage, so I asked and Sunday was fine to use it.

Go to the office, parked the Ute on L1, where we have a loading dock.
Now I didn't measure anything, nor did I have a long ramp to load it on. I thought, the loading dock has a pretty similar height to the ute, so why not roll it on.

How wrong was I. The dock is way too high. The ute had about a 50cm drop to get to. I had one shortish ramp and nothing else. Gave it a go, and yeah, i dropped it. It got stuck after the front wheel, and was gonna end in tears. Pushed it up (harder than I thought) and pulled it back.
Attempt 2. I found a long table top, that would make the approach angle doable. But it was sliding on the tray. Not gonna work.

Using an old Gorilla loading trick, I used one of the level change ramps to back the ute onto, and the table top.
An all mighty push (I couldn't get big speed as I didn't know if the table would hold the weight) and we were on.

Phew. Big phew.
I had a solid workout doing this.

Had to get some new straps, 2 on the forks, one on the rear and she wasn't going anywhere.

Getting it off at home wasn't too bad, I have a raised retaining wall edge thing that lined up very well with the side of the ute. Pushed it backwards, and then towards the garage.

Had to give it a quick hose before anything else.

ahhh that's better.

Had to get an idea what we were working with.

Pulled off the side fairings, pretty easy.

hoses generally look ok.

Found the dipstick, and man, crystal clean oil.
I'll change it anyway (once I find some) but there was plenty there and it was cleeean.

Wheels and brakes look ok.
Time to see how much is left.

Getting thin.
Maybe borderline.

Tyres look good as new. A bit firm but they are way to old to risk.

Not having the original key meant I had to swap the ignition barrel and the tank lock. Ignition was pretty easy, 2 different sized hex screws, and an easy connector. The fuel cap, wow, nightmare. Doing research online the go was to call a locksmith or pick the lock. I have no lock picking tools, nor experience, so I drilled the fucker. Finally managed to get it off.

Took the tank off, and drained the fuel and checked out the inside.

Hmm pretty nasty, how clean should it be? I'm going to rotate a few litres of fuel through it.

Took the seat off, and most of the forward fairings.

Dem quads. Looks clean from here.

Popped the new battery in. (silly terminals.)

and we have power!

all the lights work! bonus. i wasn't expecting every indicator and the headlights to power up fine, but they did just that.

Hmm, the oil was clean. Everything else seems ok, we have fuel, (but it;s dirty), meh, let's see if she kicks over:

No kick, but she turns. I'm happy with that at this point.
I was expecting a lot worse.
I've ordered a new petcock (valve under the tank) will clean it out, swap plugs and try again :)

Swapped that bent bar end too.

This is fun.
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So close, well, she's running, and stopping :)

Had to put the brake lines back on, which was a bit more of a drama than I thought, spent most of saturday on the brakes and still didn't get a result.

I was going to rebuild the front master cylinder too, to first step was to take the lever off.

and lucky I did, it was pretty filthy.

Bit of a scrub, a bit of a soak in some cleaner and she'll be good as new.

The rebuild kit is pretty simple, the screw type piston, a spring, 3 seals and circlip.

Finally got the lines bolted up, and began filling the system.
Strangely, fluid didn't really want to go through, no matter what I tried, it was barely going through my bleed hose, and all I got a was a few spurts and most of it was going back and forth, without making much progress, or even filling the pistons.
Oh well, back to youtubes to see what the go is.

Left it overnight, disconnected the top double banjo bolt, made sure I filled up the back side of the master, and pumped away, success!

fluid flowing nicely.

Filled up the cylinders, made sure I got some pressure, and bled them out again.
Brakes feel fine.

Popped the brand new top cap on, I basically had to hacksaw the old one off, and she's stopping fine.

I swapped over the old bar grips too, the old ones were an aftermarket brand, probably still ok, but fresh grips make the whole bike look and feel newer.
In my rush I managed to mix up which was meant for the throttle, and started putting the wrong one on. Once I realised it was impossible to take off, so I smashed the throttle tube. Oh well, probably a good idea to get a fresh one anyway.
Only thing, it wasn't super easy to fit. Had to take the tank off, airbox off, and free the throttle cables from the mount, and only then was there enough slack to pop it in. Phew. I am an expert at tank removal now. I'm just thankful I didn't have to take the carbs off again.

And so the brakes work, the throttle works, engine runs. Hmmm let's see how she rides.
Took it around the block (of my private property road) and yes. Feels farken fantastic. So much smoother than the 125s I rode at the Ls course, everything felt rock solid, very easy to ride too. Happy days!

I think another full day cleaning it up, putting the final few things on, and then reinstall all the fairings and time for a blue slip and rego.

Thank you Honda!
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Looking at the pics in this thread, I noticed that the instrument lights are pretty dull.

The speed is pretty much invisible above about 40km/h at night, which maybe isn't such a bad idea.
Anyway, I thought, let's see if there are some nice cheap ebay LEDs that may work here. In my travels around the interwebs, I found Ecliptech, which you may know as the guys who make the pretty awesome LED shift lights for cars and bikes. They have been around for a while, and their latest shift light is pretty solid.

It just so happens, that they had the same thought, and found/made some red LEDs specifically for the MC22 CBR250RR.

They tried various colours (no idea why, RED always wins at night) and came up with this little plug and play solution.

2 bolts hold the cluster in, and out come the 4 old bulbs, pop in the new LEDs, make sure they work,

and viola, perfect nice and bright red instruments.

I'll take a few better pics in the dark soon.

Thank you Ecliptech!
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and I've been thinking about this little engine, mine is a 1991 model, which is known at the CBR250RR - L.
Later models were a little restricted, but they all had essentially the same 249cc engine.

It runs 4 inline cylinders, of 62.25cc each.

48.5mm bore x 33.8mm stroke. A biiig shot glass is bigger.

Double overhead cams, and 11.0:1 compression.
4x 29mm carbs, on 1990 91ron fuel.

It made 45PS at 14,500rpm, and 23.5Nm at 11,500rpm.

That's 33kw. From a 1/4 litre.

Let's imagine if that was a car engine.
Say an NA 2.0 i4 like the famous B18C or a K20A from Honda.
The same state of tune for that capacity would mean that engine would make 264kw.
A serious race engine. Now I realise it doesn't exactly work like that, but it just gives you an idea of the technology in these simple little engines.
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Mostly ready.
I still have a few cosmetic things left, but I may try to get a Blue slip tomorrow. :)
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Putting the fairings and the rest of the bits and pieces on was pretty painless, it was tricky to align the rear, but the front was fine.

The rest of today was tiding up a few loose ends and making sure everything is nice and tight.
I have no idea how thorough the Blue slip inspection will be, but it won't hurt to try to get every 100%.

The Ctek battery charger I've been using has a permanent mount connector available. I've hard wired this into the battery, and left the connector plug near the rear brake master. It's hidden, yet accessible.

The shop manual specifies locktite in a few spots, so I went through those, I don't want the brakes coming loose on me.

New grips look nicer in the daylight

New mirrors too. the old ones weren't terrible, but super fragile and easily scratched, they must have been Chinaspec ones, cus the clear coat turned to dust.

The mirror and windshield frame was a little tricky to fit, it needed a few bends, but feels nice and solid now.


Are deez nuts helmet hangers? How does that work?
I cleaned up all the nuts and bolts before putting them on, can someone suggest a good clear rust proofer?
I've presently used either WD40 or Silicon lube.

Rear lights work fine, but the plastic was cracked well before I even saw the bike. I Qbonded it up as best I could, but it's still a stress point.

let's walk around.

I'm thinking a carbon exhaust may make it look too modern. Period correctness is important.
A few touch ups and that'll do it. I need the blue colour custom made I think.
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Looks fantastic! Hope you enjoy it!

May I ask what price you got it for?

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Those nut thing's are luggage tie down points.

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It was kind of abandoned, so a lucky barn find as it were?
I did track down the owner, and we came to an agreement ;)
helmet hangars are under the pilion seat. like hooks. you put one of your helmet straps on it, lock the "boot" and leave it with your bike.
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Today was rego day.
As it hasn't been registered for many years, and wore no plates, it needed a Blue Slip.
It sounds scary, but it's basically a pink slip, where they check all the numbers line up.

So this was pretty painless, a quick check that all the lights work, the brakes work, no leaks, tyres are fine, and the paperwork, and I was on my way. At $38 it's cheaper than for a car too.

Had to obviously get CTP (some weird quotes, ended up being a bit over $400 rather than $200 I first saw)
And it was time to visit ServiceNSW.

and we wait.

and wait.

and then we have plates!
I had a check of the yellow and black vs white options, and white looked a lot better. Was only $20 or so more.

Popped the plates on, and time to hit the road!

First stop was the servo, and filled it up with some nice 98. Poured in about 7 litres, so would have had about 5 of 91. Hmm how full do I fill the tank? As it's on the stand until the left side nearly touches the lip?

Riding was fine. I found a pretty good position where I was near the rear of the seat, and I could grip the ends of the tank cutouts with my knees, felt fine.
I kinda get how important sound is to a Motor bike now, you really feel at one with the engine, you dont notice the tyres as much, but the engine spinning and noise right between your legs. It's cool. Well, at times pretty hot. There was a section with a bit of bumper to bumper traffic, and with the fan running I could feel the heat working it's way up.

Everything else felt fine, front brakes work super, rear doesn't seem to do much, I guess that's the idea, they are both brand new pads (new discs up front too so needed a bit of bedding in)

Tyres felt good. I didn't lean all that much, but what I did felt super effortless.

I did notice one small issue, a bit of a knocking sound coming from the triple clamp on big bumps. I'm pretty sure it's not the shocks, it could be either the steering bearings, or the triple. I pulled in and tightened the top triple, which didn't help, or maybe a tiny bit. I need to see if I still have some coilover spanners around and tighten those two top bearing nuts. If that doesn't fix it I'll replace those bearings, and as the front end will be out, do the shocks too, which feel pretty good now.

Also heading home, the right blinker started flashing fast, I know that means, a dead bulb. I check the bulb and it was ok. Ahh, must be something else, began playing with thee wiring, and popped a 10A fuse. Oh boy, fairings off again. Not a huge deal.

When I drilled the new holes into the plastic boot tray, I brushed past the right indicator wiring. Just enough for it to short.
Pulled the wire out, taped it up, carefully put the new plate screw back in, and we are in business. I didn't want to drill the plates, so a couple new plastic holes lined it up perfectly.

went out again, more local laps, and ended up doing ~100kms.
It's pretty docile and doesn't have a lot of torque, but rev it past 10,000rpm and it transforms, and actually picks up with a bit of urgency, did that a couple of times in 1st and 2nd and was well past 80kph. Hmm careful.

Feels good man.
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First commute to the office was fine. Lovely sunny morning, had to unzip the jacket a bit it was so warm.
Safer than cycling in I reckon.
Didn't filter much will be a lot quicker when I can legally do that.

The run home was interesting, the last 5min I just got caught by the downpour,
wasn't too bad, arm sleeves and outside of the legs copped it the worst, and above 60kph rain feels like hail, but apart from that all good. #nodrops

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So it's a little tricky to start on cold mornings.
Takes a few goes.
I'm going to swap the choke pistons over (didn't do that when i was doing to carbs) and richen up the idle.
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Swapped a few bits over... and some may go back into the box.
First up was the petcock. The china one I bought was $18, worked ok, but recently I tried to turn it from On to Res and it became totally stuck in the Off position. Which is between the two options.

Totally stuck. I basically demolished the plastic turn handle, and then out vise grips on it and it still didn't move.
I've heard lots of bad things about the fake ones, and well, it wasn't too expensive.

Had to get the legit Honda one, and it's about 10x the cost, at $185, but there isn't really another option.

Popped it in, and it turns beautifully.

With the tank off I thought I'd play with the carbs again. Taking them off with the fairings is slightly more tedious, access to the lock screws is limited, but I persevered and managed to get them off.

I replaced the Choke pistons, (brand new ones) as I've been having some cold start issues.
I didn't do it when I had the carbs off last time, as I cleaned them out good and proper and thought they would be ok.

Whilst I had the carbs off, I turned out the pilot screw another 1/4 turn. I thought richening it up may help the cold start, and I thought it was running a little lean under 5k.

Took it to the local national park and it seemed to run ok.

Then, I thought, really, it pretty quiet. Let's get a shorty carbon muffler on it and see how she goes.
Man it's loud.

Also, with the stock slip on I get a bit of a flat spot around 8-10000rpm, not huge, but noticeable.
With this one, it's worse, and I can really hear it breaking up above 12k, seems to pull about the same, but doesn't sound right.

I'm gonna put the stock muffler back on and test it out again.

Does look pretty cool though.
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Sounds like you might need to put an extra washer under the carb needles to let a little more fuel flow at midrange revs?

Looks awesome! :)
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3 exhaust clips

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Bigger mains, I've even had some of these bikes with stock exhausts run better on bigger mains.
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a friend had an empty warehouse...

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wow absolutely stunning capture. lovely machine :)
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