Saturday, September 22, 2012

Strength and inspiration dropped by for a visit

Todd  Spurrier of [right]
with our shop owner Jason Brooks [left]

Today, I had the privilege of meeting Todd Spurrier, a man who is riding his Ducati Multistrada across the entirety of North America to spread awareness for a couple of genetic diseases that have affected him greatly.

Todd is an awesome dude with an awesome bike to match.

Todd was (presumably) wandering around our area looking for some good roads to ride when he stumbled upon Brooks' Cycle Center. We talked at length about some of the places he's seen, roads he's tackled and why he's on his adventure. If you're interested in the details, please email him and show your support.

Please take a minute to visit his website to get the full story.

Tuesday, September 11, 2012

Do what you love, and love what you do.

I'd like to apologize for the lack of updates to this blog lately.
Basically, I did a lot of nothing for a really long time then got a job.

I lucked out real hard and got a job as a motorcycle mechanic.
My new employer is Brooks' Cycle Center. Please check them out and if you're in the area swing by and see us.

Meanwhile, I will be cleaning out the shed, and garage, sorting tools, etc... I might post some garage porn once I'm done. After that I really need to get back on the horse with Elrich's CB750F that man has been too patient up to this point, and I really need to finish his build.

Thursday, August 9, 2012

CB125 shakedown

The CB125 seems to be up and running well. There were a couple mishaps but those got sorted out quickly.
I took the bike out for a spin to test everything out and make sure all is well.

Rest stops make good places to  put a bike through it's paces.

I think I might go up a size in the main jet. It's a 110 now but I think it could stand to be a little richer at full throttle. The pilot jet got bumped up from a 38 to a 40 and that seems to be doing nicely. That's it for now hopefully with this little guy out of the way I'll start getting some other bikes knocked out.

Tuesday, August 7, 2012

She purrs like a machine gun

I figured out the reason the CB125 wouldn't start. After many attempts the best I could do was to get it to backfire through the carb. This told me that it had to be a problem with the ignition timing but no matter what I did I couldn't get it to time correctly.

That is until I decided to take a closer look at the points advancer.
[Left] Timing advance unit from a parts CL125
[Right] Timing advance unit from my CB125
Can you spot the difference?
Looks like the advance shaft was on backwards, so off it came.
Much better.
MUCH better.

I got fired, CB125 still hasn't.

Sorry for not updating the blog. I was let go from my job on Thursday and I've been without a computer the last few days. Oh well, c'est la vie.  That just means I have more time to work on motorcycles.

Let's get you caught up to speed on the CB125:

I replaced the piston and rings, and had the cylinder bored .25 over. There was still a leak.
I replaced the exhaust valve (the one that was leaking). There was another (worse) leak.
I replace the intake valve. The leaking stopped and the motor held compression. 130ish psi.

Hells yeah.

Now that I've taken care of all that I've been trying to start the bike for a few days now. I have all the necessities: fuel, compression, spark. The valve adjustment has been performed about a half dozen times just to be ONE-HUNDRED-PERCENT sure it's right. The cam timing has been done the same number of times, and the ignition timing I lost count of somewhere around twenty.
I even pulled the motor went over everything one last time, then pulled and checked the carb, then the fuel tank (the petcock screen was a little dirty with aluminum oxide), I even replaced the carb to engine gaskets, gave the exhaust a new crush gasket and still got nothing.

Hopefully the next post will detail the awesomeness of my success and not some other catastrophic discovery.

Thursday, August 2, 2012

CB125 Head Work

So I buttoned up the motor with the new piston and leakdown tested it. I gained about 4% - putting it well into the 'acceptable' range. However it's still not quite where I want it and I can hear a definite hiss coming from the head. So off came the head and out came the exhaust valve since it was the most proximate to where the hiss was loudest.

The best way to prevent the loss of ferrous parts is to keep them bundled together with a magnet. In this case a rare earth magnet out of a harddrive.

After pulling the valve I checked for burrs, carbon buildup and any obvious damage.

The valve seats looked good and I didn't see any damage to the valve. There was a bit of carbon buildup though. The valve itself also had a bit too much play in the guide. It rocked back and forth about half a millimeter, which is WELL over the limit according to the FSM spec. A new valve will be taking its place soon.

I cleaned the carbon buildup from the exhaust ports. I'm debating on whether or not to port the intake and exhaust tunnels. 

On a very serious side note, it is always good practice to wear safety gear when working on bikes; gloves, protective glasses, etc...
Little did I know that in this case the requisite safety gear for valve spring removal includes a cup. Yes, a cup, like the ones baseball catchers and football players wear. I had the valve spring fly off and nail me straight in the barracks. That put an end to my night. Recovery beer and a good night's sleep and I should be good to go at it tomorrow.

Tuesday, July 31, 2012

.25 over the line - new CB125 piston installed.

I found a spare hour to drop the new piston into the freshly bored CB125 engine.

Saturday, July 28, 2012

I'm bored

Well that was fast. So much for the 6 week turn around time I was quoted. RB Designs had that cylinder bored out and shipped back to my door in under a week! That's exceptional by itself, and absolutely stunning when you consider that they're all the way on the west coast and I'm in VA. They must have had it bored and shipped out the same day they received it.
It looks good! I can't wait to try it out.
I owe  RB Designs  a huge thank you for knocking that out so quickly (and affordably). Also, bonus points for the fantastic packing job on everything. I feel downright embarrassed about my packing/shipping skills after seeing that.

Sunday, July 15, 2012

CB125 Cylinder Leak

So even after finding a replacement dowel for the CB125 motor, it still is not up to par. In fact it seems worse now. I pulled and inspected the rings, reassembled and measured and they seemed fine and within specs but the cylinder is now showing a 12% (best reading) loss. That's about 3% worse than before. I can hear the hiss coming from the crankcase as the cylinder bleeds air. The only logical explanation is the piston and/or rings. Rather than screw around with it any longer I'm just going to have it bored .25mm over and go from there. I'm not even going reassemble it fully to do a compression test. On the upside the head seems fine and I guess I won't be needing those new valves I bought :-/

Friday, July 13, 2012

CB125 parts motor

I pulled the motor out of the CB125 parts bike yesterday. It wasn't pretty.
Those of you with weak constitutions might want to skip this post.

Yes it's as dirty and rusty as it looks.
And yes the floor is covered in PB Blaster.
A sign on things to come. The carb is filled with mud.
The bolts came off and motor dropped out without issue.
She's dirty but seems to be in fair shape.
A bit of Simple Green a scrub brush and a hose can work wonders. 
This used to be oil.
That sure is some corrosion. The piston was rusted in place.
The valves had seen better days too.
Lots of scraping, cleaning, PB, heating, and hammering
with a socket freed the piston from it's cylindrical prison.
Think it might just need a hone?
The dowel came out easily and has found a new home in the good CB125 motor. Funny thing though, this motor was also missing a dowel; just a different one than the good motor.

Wednesday, July 11, 2012

Finding the source of the CB125 compression issue

Well I knew I wouldn't be able to sleep a wink without knowing why the hell the CB125 motor won't hold compression. Seeing as how I can use all the beauty rest I can get (I am not a pretty man) I cracked into the motor as soon as I got home this afternoon.

It took about 20 minutes to get the motor off the bike, partly because I was slacking, and partly because I got distracted a bit. Once the motor was off, the hunt was on...

It took about another 20 minutes to get the motor apart because I completely forgot that I needed to remove the rear axle to pull the rotor again.
Axle / makeshift rotor puller removed.
5 minutes later this is how she looked.
Things seem good so fa-oh wait a minute...
One... Two... Shit.

Well I somehow missed that there are supposed to be dowels around three of the cylinder studs. Probably because that one was missing to begin with.
Do I think this is the cause of my problem? Probably not, at least not entirely. I'm gonna replace it though and see how that affects things before I start boring out cylinders and cutting valve seats.

Now here's the kicker... I don't really feel like waiting 2+ weeks to get a 10x14mm dowel from Honda, and I don't have to. However, solving this issue ASAP requires me to deal with this:
Freshly hosed off, this baby is about to get torn to pieces.
Don't get me wrong, I am TOTALLY appreciative that this bike is here for the picking (props again to Bill Becker for hooking me up with this bike.) Unfortunately, the motor is completely seized and there isn't a single thing on this bike that isn't rusty, muddy, bent out of shape or all of the above. Also the lack of a center stand should make things interesting.
Given my lack of frustration so far, it's all I can do to not hang the bike by a noose around it's head and chop the motor out with a sawsall and a mechanical laugh. Before that happens though, I'm going to float the bike in some PB Blaster and call it a night. Maybe tomorrow will hold some good luck for me.