CSC Blog

So, imagine you’re a company with a hard-earned reputation for being super responsive, looking out for your riders’ best interests, and being open and honest with your customers.   Next, imagine one of your customers with roughly 15,000 miles on his motorcycle calls up and tells you that his right engine cover literally cracked open and is spewing oil.  What do you do?   Do you sit tight, cross your fingers, keep your mouth shut, and hope it never happens to anyone else?   Or, do you rapidly determine what happened, let your riders know about it, and tell them how to check their bikes so they won’t have the same problem?

You can guess where this story is going.   This actually happened.  The first thing we did when we got that phone call was to look at an engine drawing.   Based on what the customer told us and our drawing review, it looked like the crankshaft nut loosened,  ultimately came off the crankshaft, and then it (and possibly the drive gear) jammed into the right engine cover.   The next day, our customer disassembled his bike and found that was precisely what had occurred.

We quickly contacted Zongshen, as this was the first time this had occurred in North America.   Worldwide, Zongshen told us they had seen one other instance.   That sounds like this failure might be an unusual occurrence, but you know and we know that here in the US, we are racking up more miles on our bikes than anyone else.

Steve, Gerry, and I talked about this.   My RX3 (with about 12,000 miles) may be the second highest mileage RX3 in the US.  Gerry said he wanted to pull the right engine cover on my bike and check the crankshaft nut.  I rode my RX3 in this morning and we did exactly that.

Here’s what it looks like inside the RX3 engine when the right engine cover is removed…the red arrow is pointing to the crankshaft nut (Gerry had already bent the nut’s locking tab back when I shot this photo).

The good news is that the nut was in place.   The bad news is that while it was more than finger tight, it came off fairly easily and it had not been Loctited in place from the Zongshen factory.  Chances are if I continued to rack up the miles, it would ultimately loosen and suffer the same kind of failure as described above.

Here’s the bottom line:  We recommend that you pull the right side engine cover as part of your 10,000-mile service, remove the crankshaft nut, replace the locking tab, reinstall the nut with red Loctite, and torque it to 100 ft-lbs.  The tutorial below shows how to do this.

The first thing you need to do is drain the oil and the coolant.   You can see how to do this in our other maintenance tutorials.

Remove the brake lever.  To do this, pull the cotter pin and the brake actuation pin, pop the cover off the swingarm, and remove the locknut on the end of the brake lever pivot bolt.  Unscrew the brake lever pivot bolt and remove the brake pedal.

Remove the water pump.

Remove all of the bolts securing the right engine cover.  The two shown below will make you invent new cuss words when you are trying to remove them.  They are the only two Allen bolts on the right engine cover (Zongshen probably did this because they are difficult to get to), but it doesn’t really help.   They are way overtorqued from the factory, and we end up whacking on these two with a chisel to get them started.   When we replace them, we use shorter hex head bolts, which are a lot easier to get on and off.

Remove the right engine cover.

With a screwdriver, bend the crankshaft locking tab back, and then remove the crankshaft nut.

Install a new locking tab, apply red Loctite to the crankshaft nut, and torque it to 100 ft-lbs.   You’ll need to keep the crankshaft from turning when you do this.   The easiest way to do that is to use a drive on the crankshaft’s Allen socket on the left side of the engine.

After torqueing the crankshaft nut to 100 ft-lbs, bend the locking tab over one of the flats to lock the nut in place.  We start it with a chisel, and then use a channel lock pliers to bend it the rest of the way.  We then gently tap it with the chisel to snug it up against the nut.

When you do this, take care not to let the channel lock pliers touch the end of the crankshaft.  That’s a bearing surface that seals against a seal in the engine cover.  If you scratch or gouge the crankshaft end, it will create an internal oil leak.

Assembly is the reverse of disassembly, with a few things we’d like to point out.

Use a new gasket.

When you are installing the right engine over, the water pump drive has a pin that fits into its driver, as shown in the next two photos.  Take care to align the pin with the grooves in the driver.  You can turn the pump’s impeller to allow the pin to find its way into the drive.

As I said above, assembly is the reverse of disassembly.  Tighten the cover bolts to 5 ft-lbs, reinstall the brake lever assembly, reinstall the water pump cover, replace the coolant, replace the oil, and you’re good to go.

Oh, back to that first question:  What do you do…hope it never happens again or let the people who trust you (our riders) immediately know about it so they know what to check?    Hey, I work for Steve Seidner at CSC.   There was never any doubt about the answer in my mind.

Wow, we continue to pull in the press!   Rider magazine tested the 2016 RX3, and you can read their report here.

That’s what I was doing after work today, up on my favorite road.  I had the D3300 Nikon with me, too…

One of these days you’re probably going to get tired of looking at photos of my TT.  Hey, we have an app for that….send your photos to us and we’ll post them here on the CSC blog (just like we did for those Texas boys below)!

Our good buddy Joe B from Texas (not me, although I dearly miss living in the Lone Star State) sent this photo of his and four of his buddies’ TT250s just before they left on a ride…

Good times that I know well…riding a motorcycle in Texas is one of life’s great treats!

Thanks for the photo, Joe…I’m headed out to do exactly the same thing on my TT250 as soon as I’m done with this post!

My good buddy Juan Carlos Posada, editor and publisher of Colombia’s Numero Uno motorcycle magazine, published his account of our Colombian moto adventure in the latest issue of De Motos magazine!

Juan’s article is awesome, and he captured the adventure well.  I cut and pasted each section of text into the Google translator, and I thoroughly enjoyed reading it.   There are lots of color photos in the story, and that one you see above is Carlos, yours truly, and Juan in front of the Volcan Nevado del Ruiz (an active volcano high in the Andes Mountains).  It was a hoot!  That trip was the grandest moto adventure I’d ever been on…Juan, Carlos, and Enrique (of AKT Motos), thank you again.

Well done, Juan!

Folks, I’m riding.  I got my new TT today and I’m racking up the kilometers.   I’d like to say I’m racking up the miles, but you already know that story.  We’re delivering bikes, too.   The guys were in yesterday (we’re normally closed on Mondays) and we’re running flat out getting the new bikes prepped, tested, and on the way.

I rode my bike around Azusa for a bit this afternoon, I took it back in to Gerry’s guys to adjust the clutch cable and the lever angles, and then I was back out on the road.  I rode city streets and I rode the freeways.   My TT has less than 100 kilometers on it (again, I wish I was telling you that in miles) and all is well.   The TT is a torquey little thing, and it rolls away from a stop with authority.   The shifting was a little notchy initially and it was a little hard to find neutral, but pulling the slack out of the clutch cable made that better.  I still want to futz with it a bit later on tonight to get it where I want it.  It’s shifting better as the kilometers roll up.

The bike is still tight and it’s not broken in yet, so I didn’t want to beat it up too bad.  I rode my TT from the CSC plant to the University this afternoon and then I rode it home.  I saw 60 mph on one stretch of the San Berdoo Freeway when the evening rush hour traffic opened up to that speed.   The bike will do better once she’s fully broken in.  What I really liked about my new bike was sitting up tall, seeing all that was around me, and how light and maneuverable it was splitting lanes on the way home.   The TT250 is not an RX3…it doesn’t have the same high end rush, it’s not fuel injected or water cooled, it’s a 5-speed, and it costs less than half of what an RX3 does.  It’s a hell of a bike, though, and I’m having no regrets with mine (other than that kilometer thing).   I’m going to adjust the angle of the levers again after dinner and get back up in the mountains to put a few more kilometers on it.

We’re working a half dozen quality details with Zongshen on the TT250 right now.   It’s one thing to evaluate a few prototypes; it’s an altogether different challenge when multiple shipping containers arrive with tons of new motorcycles in them.   There are a few things we’re giving the Zong factory a tuneup on, we’re making sure the bikes are right for you, and they are shipping out of Azusa sharply.

You’re probably asking…what, no photos?   Not yet, but stay tuned.

I picked up my new TT250 this morning and I was hoping I’d be able to get on the blog and brag about it nonstop…but I can’t.  The good news is that the speedometer is indeed calibrated in miles per hour, and when I ran it by one of those “your speed is” electric signs it was right on the money.   The sign said 39 mph (I was in a 40 mph zone), and my speedo said 39 mph.  Wow, I thought…this is more accurate than the RX3 speedo.  Then I looked at the odometer and the tripmeter, and they were whirling.   Uh oh.  Steve told me our good buddy Jim, who picked up his bike on Saturday, questioned the same thing.  I took out my cell phone, got on Google maps, and saw that I was 3.5 miles from the plant.  I reset the tripmeter to 0.0 miles and rode back to the plant.   The tripmeter indicated 5.5.   That’s kilometers, folks.  It looks like the Big Zong got the speedo right, but they neglected to recalibrate the odo and tripmeter.

It’s an annoyance and an engineering change control lapse, and we apologize for that.   We’ll make good on it.  I don’t have the details on what we’re going to do yet as I only just confirmed this today, but I can’t see how it could possibly be anything other than replacing the entire speedometer.   We’re talking to the guys in Chongqing, and I’ll let you know as soon as we know.   But don’t fret.   Like I said above, we’ll make good on it.

Our good buddies Sue and Andrew both bought RX3s, they are both authors, and they are both awesome.  Check out this video Sue just posted on YouTube…

Sue and Andrew are doing Alaska on their RX3s this summer.  I believe they are going to be the first to make that trek, and I’m sure there’s a book in that one.  Guys, sign me up…I want an autographed copy!

I’ve read a number of posts on a couple of Internet forums lately about fuel in the RX3’s crankcase oil.

I had never noticed a fuel smell from the oil before on any of the motorcycles I previously owned, so I asked Zongshen’s engineers about this phenomenon.   They explained to me that it is a normal occurrence.   In fact, they told me a fairly high percentage of fuel in the oil is expected as a normal part of the engine’s operation.

Here’s what’s going on:  In the early stages of the fuel injection cycle, some of the injected fuel does not atomize completely.  When that occurs, a small amount of raw fuel washes down around the rings and finds its way into the crankcase.   Ultimately, as the engine reaches operating temperature, most (but not all) of this fuel will vaporize and either be sucked back through the intake tract, or it will condense and go into the drain tube beneath the oil/air separator.

As a check on the guidance offered by Zongshen, I did a literature search on my own at the California State Polytechnic University (I teach in the College of Engineering there).   There’s not a lot of information on this issue, but what information there is supports what Zongshen tells us.   In particular, here’s the conclusion from a technical paper in which the researchers focused on this topic for both diesel and gasoline engines:

The obtained results are in agreement with the relevant published data for fuel-engine oil mixtures, where amounts of fuels in oils of up to 4 or 5% are foreseen as acceptable levels, while amounts of 7 to 10% of fuels in oils are considered as unacceptable levels.

Someone on one of the forums wondered aloud if my recent blog describing improved smoothness and performance with 20W-50 oil was related to any of the above.  Folks, it was not.   We’re not that devious…if we have a reason for stating something we won’t hide it from you.   Not surprisingly, my literature search indicated there is some viscosity reduction as a result of fuel in the engine oil.  This is acceptable within the fuel-in-the-oil levels indicated above for both 10W-40 and 20W-50 oil.  The literature indicates that a higher viscosity oil (the 20W-50) will have higher remaining viscosity than would a lower viscosity oil (the 10W-40) if fuel is present in the oil.  That’s entirely logical, but it wasn’t the reason I mentioned that my bike runs better with 20W-50 oil.  I mentioned that because, well, the bike runs better with the 20W-50.

The significant point from all of the above is that fuel in the oil is normal, as both Zongshen and the engineering literature tell us.