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Old 06-14-2019, 07:38 PM   #1
Gaijin   Gaijin is offline
 
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RX3 recommendations June 2019?

Hi, I'm joining the RX3 family next week, picking up a used one. I've been reading everything I can, and I have to say this forum is simply outstanding. But so much of the interesting content was put up in maybe 2015 or 2016, so I'm just checking on a few things so see if anything's changed or these things are still recommended now?

1. Oil change and oil filter. The bike is a 2018, with under 500 miles. I'm thinking of changing the oil before riding it much. Is there any cross-compatible oil filter available in the US, or a HiFlo model or anything?


2. Sprockets. At one point Spud had highly endorsed a 13T/46T combination. Is that still the way to go? Does it impair highway speed much? Intended use is lots of trails and highway to/from those trails.



3. Big bore kit. Read a few glowing reviews on the 283cc big bore kit, and I can see adding that after the warranty runs out. But there was also a 300cc kit, and I don't think I've seen any reviews on that. Has the 283cc proven reliable? Has the 300cc proven reliable? Would you go for one now?


4. SpeedoDRD. I have one on my Benelli and love it, and plan to get one for the RX3. The review from 2015 says that none of the other DRD models fit the RX3. I found that the H1 model fit my Benelli, even though there's no good reason why it should, I guess. Here we are in 2019 -- is there a confirmed SpeedoDRD that fits the RX3? Or do we still have to splice wires?


5. Overheating. I think it was Spud or someone else said they ran into overheating with the 283cc kit. I ride in HOT climates a lot. Has overheating been an issue? Is it limited to the big-bore kit bikes? And has something arisen in the last few years that resolves it?


Thank you very much for any assistance you can offer!


 
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Old 06-14-2019, 09:28 PM   #2
dpl096   dpl096 is offline
 
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Welcome aboard and congratulations on the purchase. The RX3 is a really fun bike to ride. In regards to the oil filter... I switched to the metal reusable one and loved it. In the long run it'll save you money ....IMO. I bought mine on AliExpress.

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Old 06-15-2019, 04:03 PM   #3
pyoungbl   pyoungbl is offline
 
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1. Oil is cheap. I'd change it unless you are convinced the PO already did so. The filters are not compatible with anything I have found locally. I bought a bunch from CSC.

2. Before you go to changing sprockets you should ride the bike and see if the stock setup meets your needs. The countershaft sprocket is torqued down quite a bit and I found it to be a real PITA to remove. The rear sprocket is much easier. If you change sprockets you may as well install a good aftermarket chain. The OEM chain is a known cost cutting item. The engine does not generate much oomph until it hits about 4K rpm. You can gear the bike so that 4-7K range is anywhere you want it. You will trade between torque at low speed or at high speed, your choice. You cannot have both.

3. Big bore kit. Once again, ride the bike stock. I find the stock setup to be OK.

4. I use my GPS to calculate speed. My front wheel is a 19" (as found on the 2018 bikes?) and the speedo is fairly close to reality. Of course that changes as the tire wears.

5. Overheating...I'm in coastal Virginia where it gets too darn hot in the summer. Even with stop and go traffic I have never had a problem with overheating. Yes, the fan will come on and the hot air blowing back is noteworthy but the truth is I wimp out long before the bike overheats. The dual radiators are quite good at shedding heat. FWIW, I actually found that my bike runs too cool most of the time so I installed a higher temp thermostat.


 
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Old 06-15-2019, 08:13 PM   #4
Jay In Milpitas   Jay In Milpitas is offline
 
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Hi Gaijin.

Riding a Benelli indicates you are an experienced rider, and with that comes knowing that each machine has it's pros, cons, and limitations.

I've not gone to a big bore simply because I've learned over the decades that trying to make a bike something that it is not, just consumes money that could be more wisely invested in a more suitable bike. The RX3 is a quite capable 250. Change sprockets, change bars & seat and such to suit your comfort, but don't try to make it a budget KLR or DR 650.

If there is an alternate paper filter, I am not aware of it. As DPL096 has said, some have gone over to a washable metal filter. I have chosen to continue to order filters in the six-pack from CSC primarily because I believe in supporting the company (and the owner) that invested the money and effort to get the bike(s) emissions certified, upload the tutorials, and keep parts in stock (far better than my local Honda dealers) for us.

The only overheating incidents I recall were from low coolant levels. The whole system of 2 radiators, hoses and engine only take about 1 liter of fluid, so keeping it full is essential. As Peter said, they tend to run cool and a higher temp 'stat is a good idea to keep the engine happy, boil off water from the oil, and make the fuel injection run optimum. Note to self: I really should do Peter's upgrade.

Hope this helps. Happy riding.
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Old 06-15-2019, 08:22 PM   #5
Gaijin   Gaijin is offline
 
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Thanks for the responses!


Quote:
I switched to the metal reusable one and loved it. In the long run it'll save you money ....IMO
Interesting; I'll look for more reports on that. My immediate concern was trying to find one in stock somewhere so I could change it before starting the 1335-mile trip home; so far I haven't found the metal one anywhere although (see below) I have resolved the issue for now.



Quote:
1. Oil is cheap. I'd change it unless you are convinced the PO already did so. The filters are not compatible with anything I have found locally. I bought a bunch from CSC.
I definitely plan on changing the oil when picking it up; my biggest concern was in finding an oil filter. Fortunately CSC agreed to ship one to an unaffiliated dealer that will be on my route home, so I can change it properly in the parking lot! Kudos to Rio Grande Motosports for agreeing to receive the package and hold it for me.


As for "riding the bike first", I totally understand, and the trip home alone is going to be 1,335 miles, so yes I'll know the bike pretty well by then. I agree about changing the chain with the sprockets, most definitely.


Quote:
The engine does not generate much oomph until it hits about 4K rpm. You can gear the bike so that 4-7K range is anywhere you want it. You will trade between torque at low speed or at high speed, your choice. You cannot have both.
Understood. For reference, I have a Harley with an 1868cc engine that has diesel truck-style torque over the entire powerband, and a Benelli TNT135 that has pretty much zero torque anywhere. I am expecting the RX3 to be much more like the Benelli. What I have found on the Benelli is that the stock bike can't come close to pulling redline in top gear. Because of that, it pretty much makes sense to go to a 1-tooth smaller sprocket on the small engine, because you won't be giving up any actual top-end speed (although the engine will run higher RPM at any speed). If the RX3 is the same way, and knowing that I'll want low-end torque for hill climbing, Spud's 13/46 seemed to make sense. But yes, I'll give it a good long run-in before actually changing the sprockets.



Mainly I'm going to be ordering oil filters in bulk from CSC, and if I put the sprockets on there it gets me close to the $100 for free shipping, so I'm basically asking "why not"?



Quote:
My front wheel is a 19" (as found on the 2018 bikes?) and the speedo is fairly close to reality.
As for the speedo, I used a GPS to calculate the speed overrun on my Benelli, and it was about 12% in error, and I read here where Spud found the RX3 to be about 13% in error or so. But IINM, Spud's front wheel was 18". Maybe the speedo is much more accurate with the 19" as you say, and this is effectively a non-issue! I *think* the 2018 has the 19" wheel stock... not sure...


Glad to hear the report on overheating. I lived in coastal NC and the summers were oppressively hot, and I'm in Texas now which is even hotter, but it's more of a humidity heat than it is truly high temperatures (like 117+ in Vegas/Arizona, vs. about 102 here) so maybe it's not anything to worry about.


 
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Old 06-16-2019, 11:37 AM   #6
calvarez   calvarez is offline
 
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1. No other options, and the metal ones aren't really a filter so I would strongly recommend against it. They're just a screen to catch chunks, which the bike already also has. Order a kit from Tako here on the forum and you'll be good.

2. I went a tooth down on the front and love it. Highly recommend it.

4. I installed the universal one, works great, easy install.


 
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Old 06-16-2019, 05:37 PM   #7
Jay In Milpitas   Jay In Milpitas is offline
 
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Quote:
Originally Posted by Gaijin View Post
Fortunately CSC agreed to ship one to an unaffiliated dealer that will be on my route home,
And that is precisely what makes Steve Seidner and CSC a class act.
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Old 06-16-2019, 10:30 PM   #8
Gaijin   Gaijin is offline
 
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Quote:
Originally Posted by Jay In Milpitas View Post
Riding a Benelli indicates you are an experienced rider, and with that comes knowing that each machine has it's pros, cons, and limitations.
Most definitely. Experienced, yes, 40 years riding on and off. And I hope I've adequately researched the RX3 to be aware of its limitations. I know some bought it with high expectations and were disappointed; I hope to have the opposite experience.


Quote:
I've not gone to a big bore simply because I've learned over the decades that trying to make a bike something that it is not, just consumes money that could be more wisely invested in a more suitable bike.
You're speaking the truth. I'm a customizer and modifier, I can't help it, but I was looking at adding a 124 kit to my Harley and the cost, when all was said and done, would have been upwards of six thousand dollars. I got the RX3 for less than half that, and hopefully opened up a new field of riding in my garage.


That said... two hundred bucks for the big bore kit... it calls to me...



Quote:
but don't try to make it a budget KLR or DR 650.
Again, agreed. I'm more of a mind that I'll make it the best RX3 it can be, with the understanding that some parts make things worse if not done right. The big bore kit caught my eye because someone (maybe nzbrakelathes) said that it actually ships as a stock 283cc engine in other models, so that sounded promising.


Quote:
I have chosen to continue to order filters in the six-pack from CSC primarily because I believe in supporting the company (and the owner) that invested the money and effort to get the bike(s) emissions certified, upload the tutorials, and keep parts in stock (far better than my local Honda dealers) for us.
I agree with supporting local dealerships and importers that bring fun new things like this to us. My experience with CSC has already been very good, and I'm not even an owner yet. I'll be ordering the filters in bulk; I was just trying to get one right away as I don't want to run up 1300 more miles on the original filter. As said, CSC is making it happen, so it's all good.


Quote:
Hope this helps. Happy riding.
Thanks!


 
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Old 06-16-2019, 10:33 PM   #9
Gaijin   Gaijin is offline
 
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Quote:
Originally Posted by calvarez View Post
1. No other options, and the metal ones aren't really a filter so I would strongly recommend against it. They're just a screen to catch chunks, which the bike already also has.
That's the impression I got, but others have been happy with them so I wasn't sure. I've always used paper filters before. I saw that some other NC250 bikes out there (primarily dirt bikes) don't seem to even offer the paper filter, they only use the screen.



Quote:
Order a kit from Tako here on the forum and you'll be good.
Sorry, I don't know exactly what you mean. Is Tako nzbrakelathes? Or is Tako another supplier that I haven't encountered yet?


Quote:
2. I went a tooth down on the front and love it. Highly recommend it.
CSC recommends it too, specifically for offroad work. Question: can you pull redline in top gear with the smaller front sprocket?


Quote:
4. I installed the universal one, works great, easy install.
Thanks. I'm sure that's the way I'll go.


 
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Old 06-17-2019, 08:27 AM   #10
NzBrakelathes   NzBrakelathes is offline
 
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Quote:
Originally Posted by Gaijin View Post
That's the impression I got, but others have been happy with them so I wasn't sure. I've always used paper filters before. I saw that some other NC250 bikes out there (primarily dirt bikes) don't seem to even offer the paper filter, they only use the screen.




Sorry, I don't know exactly what you mean. Is Tako nzbrakelathes? Or is Tako another supplier that I haven't encountered yet?



CSC recommends it too, specifically for offroad work. Question: can you pull redline in top gear with the smaller front sprocket?



Thanks. I'm sure that's the way I'll go.
Check my eBay below - I have several RX3 items there and parts I can order in specially for you etc.
CSC isn’t always good or bad but you have choices etc


 
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Old 06-17-2019, 12:28 PM   #11
Gaijin   Gaijin is offline
 
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Quote:
Check my eBay below
I've already been corresponding with you on ebay, we've exchanged a few PMs. Very interested in the brake upgrade for the front, as the stiff/weak front brake was mentioned in several reviews. Has that been changed for the '18+ model years, or do you have any reviews on your upgraded brake?


 
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Old 06-17-2019, 07:20 PM   #12
calvarez   calvarez is offline
 
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Yeah, that's your guy. The filter kit has everything you need and more. Reliable shipping and service, good deal.


 
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Old 06-19-2019, 03:46 PM   #13
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The SpeedoDRD works you have to cut the plug and solder the wires it was about 10% with my kenda's. I like to know how fast or slow the mighty Zong is really going. Ride it first before you change sprockets it did not take me long to find out my zong was geared to high for me just going to 13th front sprocket was the single best thing i did for my to fast blue
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Old 06-19-2019, 11:59 PM   #14
JunkyardDog   JunkyardDog is offline
 
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I have no experience with the RX3 (yet) but I do have quite a bit of experience with big bore kits, and my advice is don't. The bottom end and transmission were not designed for more power. More power equals more stress on engine parts. In every case where I have installed a big bore kit, it has noticeably shortened the life of the engine, decreased reliability, and in some cases broken the engine. I gave up. My feeling now is if you need more power, get a bigger bike where the whole engine and transmission is designed to handle the power it makes.


 
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Old 06-20-2019, 10:32 AM   #15
2LZ   2LZ is offline
 
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Quote:
Originally Posted by JunkyardDog View Post
I have no experience with the RX3 (yet) but I do have quite a bit of experience with big bore kits, and my advice is don't. The bottom end and transmission were not designed for more power. More power equals more stress on engine parts. In every case where I have installed a big bore kit, it has noticeably shortened the life of the engine, decreased reliability, and in some cases broken the engine. I gave up. My feeling now is if you need more power, get a bigger bike where the whole engine and transmission is designed to handle the power it makes.
Actually, the NC250 motor was designed with more power, which you will find in the Gasgas, Pitster Pro and others. The NC250 in the RX3 was tuned down for the US market, EPA and CARB. The RX3 comes in at about 25+ HP and the same motor in other bikes I believe has 32(?) hp. I'm sure someone will chime with the exact stats.

The big bore kit on the RX3 does nothing for the top end. The EFI and ECM really limit the bike. What it does do is wake up the mid-range and most importantly, it makes between 3500-5000 RPM's usable. These bikes are anemic below 5000 rpm's in stock form.

I agree with you regarding really pushing the power out of a motor, especially since a modded motor is usually ridden harder but in this particular case, I really don't think the big bore kit even stresses it past its original design HP. I wish it would! ;-)
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