Skip to content
2018 Beta 390RR-S Two year review

2018 Beta 390RR-S Two year review

My 2018 Beta 390 RR-S doesn’t look as shiny after 2 years of hard riding and unfortunate repairs but I still have a soft spot for what really should be a great bike - If I could just keep it running.

Why Beta

I got into Enduro after more than a decade of riding sport bikes on-street (and arrogantly proclaiming that street riding was the real deal while dirt bikes were just a side-show). My first off-road adventure came atop a spare 96 DR200 my brother had lying around. The DR barely pulled me up the small hills near my house but after only an hour in the saddle, I was hooked. Despite its dinky performance, I immediately regretted all those years of holding out.

Wanting my own dirt bike, but short on cash, I picked up an 87 XR600 with a leaking engine case and poorly adjusted carb. It was as ugly as the seven sins, weighed more than a Panzer, and took longer to start than I spent riding it most days; but it didn’t matter, I rode the shit out of it.

2018 Beta 390RR-S Two year review — Figure 2

1987 XR600 with Dual Sport Kit and 80% street tires

The joy of riding older bikes, especially ones that don’t cost much to replace, is that it’s not a big deal if you break them. This is doubly true as a newbie rider with no clue what I was doing. I threw the XR off cliffs, headlong into boulders>, and occasionally right over my head - with almost zero consequences. 

Sadly, no bike lasts forever and my abuse of the XR finally caught up to me. I sold it for $500 (it could be rebuilt well enough) and went looking for a replacement. This time I wanted something nice. Had to have e-start (no more kicking for days after flooding the carb on a failed hill climb), had to be light enough to handle on the rocks, and, if possible, needed some style.

After literally months of agonizing over the options (DRZ, CR500, Husky, KTM, Used, New, 4T, 2T, plated, off-road) I finally settled on the Beta 390 RRS. It seemed perfect. Cool niche styling that would stand out on the trail. Competitive feature set (suspension, power, equipment). It was even priced slightly under the big two and the BYOB suited my ego perfectly.


To their credit, Beta has a really fun buying process. You go online, pickout all your dream parts, and with just a deposit, the bike heads to the dealer for you to finance and take home. I hooked mine up! Skid plate, hand guards, upgraded rear shock, samco hose kit, tuned suspension for my weight, shark fin, disk guard, sprocket guard, pipe guard, brake cylinder brace, all the stuff I knew I was going to bang up within a week.

2018 Beta 390RR-S Two year review — Figure 3

Picking up my brand new 2018 Beta 390RR-S

It didn’t take all that long for Beta to get it all together and shipped and within a few weeks I hit the trail to test ride my new bike. After struggling around on the XR600 for so long, I was sure the Beta would turn me into Graham Jarvis. 

Nothing but (Mechanical) Trouble

Thirty minutes into my second ride, with a mere 13 miles on the odometer, the Beta clutch failed just as I crested the top of what I think was my 4th small hill climb on the bike. I almost cried. IT”S A BRAND NEW BIKE! How could it be broken already? Two hours of truck work later, I had the bike back in my garage with the clutch cover open. The plates were fried. As in completely melted down.


The weird thing was, there just didn’t seem to be any good reason for the failure. The bike had oil, I was following the break in procedures at the time, there wasn’t any noticeable fade or slipping (up until it failed). It just didn’t make any sense. Fortunately, the dealer agreed with me and despite the clutch being considered a consumable part, Beta authorized a warranty replacement. Within a few days I was back on the trail, happily assuming the issue was a one-off. 

Death by 1000 Cuts

It wasn’t long, however, before I started to notice lots of little failures.

Fuel Light - The fuel warning light started coming on randomly (even with a full tank of gas), rendering it pretty much useless as a guide during longer rides. 

Evap Canister - In the middle of one hard enduro crawl, the bike suddenly refused to idle without stalling. After some trail-side tinkering, I discovered that removing the charcoal canister vacuum tubing resolved the issue. I eventually followed the advice of fellow YouTuber Vicki P> and just plugged the vacuum inlet on the engine to permanently solve the issue. 

Battery - I endlessly had trouble with the Beta battery. The factory lead-acid battery lasted about a year before slowly and annoyingly failing. I replaced it with an expensive Lithium battery that barely lasted 3 months before dying completely. To avoid future problems, I installed the Beta Factory kickstarter kit ($400) thinking I’d just kick it over if the battery ever died again. 

Instead, I discovered a major drawback of electronically controlled fuel injected engines. If the battery dies, you cannot easily kick (or bump) start these bikes.  Lithium is nice in that it works all the way to the last volt, but once it’s dead, it’s really dead. 

In order to get enough voltage flowing to charge the fuel pump and open the injectors, you have to run the bike downhill for 30-50 feet with the engine cranking and the stator churning. No amount of kicking it will ever get you enough voltage to trigger the fuel pump. To make matters worse, the Beta is extremely hard to kick over. It does not have any kind of decomp system (at least not one that you can engage for kickstarting); and this is coming from a guy who spent 2 years riding  kickstarting an XR600.

As a compromise solution, I went back to a lead-acid battery. When it did eventually die on me because of too many starts on a hard hill section, I was actually able to kickstart it back to life. Even though it didn’t have the juice to crank the engine, there was just enough left in the cells to power the fuel pump. 

Radiator Leaks - The Beta comes stock with a relatively small fuel tank and while it’s great for weight savings, it doesn’t do much to protect the radiators. This means each radiator sticks out to the sides of the bike further than almost any other part (except the handle bars). As a result, every little fall lands on the radiators. I had guards installed as part of the BYOB deal, but they just don’t hold up. After several months of riding, my radiators were so banged up and twisted I had to start patching holes.


Front Fork Guards - The stock front fork guards are pretty weak and lack the extra rear bracing strap you find on a lot of enduro bikes (like KTM). As a result, they don’t do a lot to protect against real falls. This wasn't a big deal for me, until I accidently dragged the bike off a rock-hop the wrong way and nicked the tubbing. Two months later the fork seal was leaking. A special order part and $400 later, I was back at it but it taught me to be more careful because aftermarket parts are just not available. 

Clutch Failure #2

About eight months into owning the bike, my clutch started hanging up in the middle of Malcom Smith Trail in Big Bear - right at the gnarly section near the top. We got the bike out ok, but upon tearing into the engine I found that just about the entire clutch stack had blown up.

2018 Beta 390RR-S Two year review — Figure 4

Fragments of shatter clutch friction plates are visible both inside the basket and floating under it.

Again, the clutch failure did not have a clear cause. There was always oil in the engine, I wasn’t riding the bike any differently than I’d ridden other bikes. There wasn’t any abuse. To be sure, I slip the clutch to control power delivery and traction at the rear-wheel, just like all good riders. But it wasn’t done in a way that could explain these repeated failures. 

This time, I went all in on replacements. The stock Beta steel plates use ridiculously small tabs that fit into half-tube sliders to engage the inner basket (shown in the photo above). The setup was new for the 2018 Betas and was supposed to improve feel or something like that. While it’s a terrible system that I highly recommend you change ASAP, I do not think it’s responsible for my clutch issues. If it was just the design, they’d all be failing and I don’t find many stories of these problems outside of my own experience. 

Just to be safe, I ordered Beta’s “Factory Clutch Race Kit”> which replaces the slide tubes and steel plates with a better version that is much more durable. I also replaced the entire basket (I broke a spline trying to torque the first one) and of course, all new friction plates straight from the dealer (at twice what a clutch should cost).

Clutch Failure #3

You would think 3 failures in two years (only 10k miles of riding) would be nearly impossible, but not so. Almost exactly 6 months after fully tearing down and rebuilding the entire clutch setup, I was once again noticing dragging and slippage, this time during our Moto backpacking trip>. Fortunately, the bike made it back without serious issues, but experience had taught me to be cautious and I opened up the engine yet again to see what was going on this time. 

Sure enough, the clutch plates had once more melted down. This time, however, I’d caught it early and only the outermost plate was damaged. 

Just as before, I couldn’t identify any specific cause. It wasn’t that the friction plate had worn out, there was lots of life theoretically left in the pad materials. But they’d melted, clearly an early failure and one that sure looked like it was being badly mistreated.

2018 Beta 390RR-S Two year review — Figure 5

Melted friction pads on this outer clutch plate appear to be badly abused.

Thermostats and Samco Hoses

As the Beta’s clutch problems piled up, I shifted to considering more out-of-the-box culprits. As part of the BYOB, I had elected to install the Samco silicone hose kit. On recommendation of the dealer, I went with the style that deletes the stock thermostat housing. It seems that some riders have had issues with the housing cracking during rides and catastrophically leaking coolant. When I asked about engine operating temps, the dealer assured me it wasn’t an issue. 

Through my time with the Beta, I had noticed that in anything but the hottest of summer days, the engine consistently ran cold. Like really cold. Cruising on pavement it could barely break 130 degrees if I worked it out a bit and even at slower single-track paces, I routinely had operating temperatures in the 150s and 160s with small increases during hill climbs. 

The stock thermostat is set to around 180 degrees. Which means that on a good day, I was running the bike at ~80% of its intended engine temperature. Of course, during hot days, this wasn’t such an issue, but as soon as the weather cracked cooler, the engine temp would drop accordingly. For the first several months, I shrugged this off figuring the dealer knew what they were talking about. 

But, after losing the 3rd clutch in two years, I finally decided I could no longer ignore the problem and decided to revert to the stock thermostat setup. My working theory is that the dramatically lower oil temp increases viscosity and puts extra strain on the clutch plates leading to additional drag, heat, and ultimately melted friction plates.

Limited Aftermarket support

Unfortunately, going back to stock wasn’t so easy - or cheap. I’d never actually had the original thermostat housing or tubing, just the Samco kit. While I liked the silicon lines well enough, I had no way to easily insert the necessary extra routes. To make matters worse, I had long ago plugged the radiator output stub that was supposed to supply the thermostat, which meant either a major wielding job that I wasn’t qualified for, or a new radiator. 

I tried hunting online for an aftermarket or used radiator but couldn’t find a single part for the right year (though I now suspect older radiators might work ok since Beta seems to have changed the setup for 2020 to a more KTM style cross pipe layout). The bike was just too new and too niche. Nobody made parts for it, and there were so few on the market that no one had spares either. In fact, no shop I searched even carried the OEM parts. 

In the end, I called up Mylers Radiators> and asked if they’d make one for me. They obliged and $200 later I had my replacement radiator with proper inputs. I also had to choose between buying each individual piece of tubing from the dealer or going with the Samco kit designed for use with the stock thermostat. I went with Samco as their stuff had held up well so far. Unfortunately, I could only get the complete hose kit for another $200. I also had to special order a thermostat assembly from the dealer. This was a surprisingly affordable $65 with everything included. 

Making it all fit

With much effort, I finally figured out how to route all the tubing to include the new thermostat (I had never seen how the original stock part was placed or connected and could not find a diagram of the hoses). 

Unfortunately, the Myler radiator was overbuilt (it was “reinforced”) and took up an 1/8th inch more space than stock. This left precious little room for the thermostat housing. I got it all on, but the thermostat was touching the radiator in a way that made me a little worried it would damage it in a fall (remember, the radiators are the first thing to hit the ground on these bikes). 

Frustrated, I left it and went riding. Twenty minutes into the hills, I tipped the bike over on an extremely steep descent and despite the soft dirt, punched a hole in the new radiator. 

Coolant spewing with every twist of the throttle, I drove the bike home and just about dumped it in the trash on the spot.

2018 Beta 390RR-S Two year review — Figure 6

The new Myler Radiator is nice, but also a little thicker than stock which makes space tight.

Calling it quits?

I was pissed. I’d so far spent at least $2000 repairing early failures and replacing parts that should never have been removed (I finally hear you thermostat gods). It dawned on me that I could have picked up an unplated KTM 300 two stroke for little more than I’d so far spent trying to keep the Beta running. And what had I really gotten out of the damn Italian Prince? Not so much. I hadn’t turned into Cody Webb, and approaching 40, was realizing no bike was going to get me there. I was seriously doubting the ROI of spending so much on the machine when it wasn’t really delivering its end of the deal.

Back to My (XR) Roots

Frustrated, and not wanting to make another vanity buy that might be equally disappointing, I decided to try going back to basics in order to figure out what I really wanted in a bike. I quickly found a mint condition 99 XR400 on Facebook Marketplace for just $2700 and picked it up that weekend. Sure, it was heavy as hell and hard as fuck to start, but there was that joy again. That feeling that it didn’t matter if it broke (not that it would, they’re bullet proof) because it hadn’t cost much to start with and was relatively easy to fix (with plenty of used parts lying around). 

I kitted the bike with some armor and hit the trails. It took me several rides to really get the hang of the taller heavier bike again. I was pleased to discover that the famous XR kickstart technique came back to me quickly (it helps that you spend most of your life practicing that skill). 

Testing at Soboba

A few weeks later, the team hit the Soboba group ride and I brought along the XR400>. Kids laughed, old guys complimented my “verve”, and I ended up having kind of a miserable time. I was out of practice on the bike, which made me slow. The weight started to tire me out early, and I quickly fell behind our group. I forced myself through most of the black diamond sections of the ride, but it was brutal. At one point, all alone near the back of the entire 200+ group I finally flamed out. A small section of hill climb was kicking my ass. I’d tried twice but, being tired, messed up the technique and dropped the bike back down, twice. This of course flooded it out and I’d already spent maybe 10 minutes trying to kick it back to life (twice). 

When I finally got the bike running for the third time, I was done. I cut back out to the easy section and plodded on back to the trucks a full hour behind my buddies. 

Let’s try the desert

Not at all sure what to do next, I took the bike with me to the annual camping trip we take each year to the Joshua Tree area. It’s a great weekend with lots of riding on unforgiving desert terrain>. The XR did ok, taking me everywhere the group went but I felt like I was double earning every mile of it. I was consistently in the back, mostly because it took me forever to get the bike running if I dropped it (which happened a lot when you’re riding hard enduro on desert rocks). 

Near the end of the trip, I got stumped by a difficult climb. Part way up, tired out and frustrated, I got angry and dropped the bike. On the way down, I landed on a cactus that went all the way through my thumb and decided I was done. I sat at the bottom of the hill for something like 20 minutes contemplating just riding back on my own (everyone else was up top waiting patiently).

Not quite willing to give up, I gritted my teeth and made one more attempt, this time managing to get all the way up. I’d made it so far, but I was starting to doubt my choices yet again. 

I did spend some time riding a couple of KTM 300s that weekend and really enjoyed the performance of them. But it’s hard to get one plated and I’m still torn as to how to proceed. 

What’s next for the Beta

I’m not sure what I’ll do next. I had fully planned to sell the Beta once I repaired the radiator leak. But after watching myself flop around on the XR during the Soboba ride (you can see me struggling in a few of the rider videos that have gone up), I’m having second thoughts about abandoning the Italian bike. 

At this point, I’ll probably give the Beta another try. I’ve fixed the thermostat placement issue and will soon post a video of how to repair radiator leaks with brazing rod. I’d kinda like to see if the thermostat (and higher engine temp) solve the clutch issue. If not, I’m almost certainly going to dump the Beta and go KTM, but until I’m sure, the engineer in me wants to keep testing, just in case. That's the true spirit of a WannaBe!!

Whatever happens, we’ll be sure to post about it. And watch for the corresponding Beta 390 ride review video we’re planning shortly.

Older Post
Newer Post

1 comment

  • Hi i have beta 390 racing 2018 now has 300 hours.When you make rebuild the engine and in 300 hours what you replace
    Extreme Sports WannaBes replied:
    That’s a great question. I actually sold my Beta before I had to do a rebuild. I’m not riding a KTM 500 EXC-F. I’ll have a video and blog article up soon on some repairs I ’ve done to the KTM such as new piston rings, but I have not done a full rebuild yet.

    Neokles Chrysostomou

Leave a comment

Please note, comments must be approved before they are published

You may also enjoy

Scott Strike eRIDE 930 eMTB | Electric Mountain Bike Review, Unboxing & First Ride | Enduro Cycling

Before you start telling us that e-bikes are cheating, let me remind you that we are the “WannaBes”, and, since we have no intent on going into professional mountain biking there is no such thing as cheating. Get over it, and remember that riding anything is supposed to be fun...

Fly Trekker and Kinetic Helmet Chin Mounts For GoPro Hero, DJI Osmo, Insta360 Action Cameras

While the mission to equip everyone with the ultimate action camera mount will forever be ongoing, it is nice to feel a sense of completion every once in a while. Over at WannaBes world HQ, we are basking in the glow of ticking the last two boxes as we introduce the final chin mounts for the Fly line of helmets - The Trekker for you ADV riders out there, and the Kinetic for those that prefer that their tires stay more or less in the dirt.

How to Check & Adjust 2021 KTM 500 EXC-F Shim Valves | 130 Hour 4 Stroke Dirt Bike Maintenance

Kjeld isn’t lazy, he just put off all maintenance on his KTM 500 EXC-F for about 130 hours...
Close (esc)


Use this popup to embed a mailing list sign up form. Alternatively use it as a simple call to action with a link to a product or a page.

Age verification

By clicking enter you are verifying that you are old enough to consume alcohol.


Your cart is currently empty.
Shop now