sportsawyer

The stop plate doesn't use both stop bolt positions, it uses the forward stop bolt and the "protector" bolt position. The protectors don't come on 3ED / 4ED models, but the threaded holes are there in the swingarm. If you tried to use the protector bolt hole as a cam stop hole, it wouldn't work. The axle would slide all the way forward and the cam wouldn't contact the stop bolt in the protector hole. Look closely, what the plate does is creates a stop location half-way between the normal two stop locations.

I've seen those stops, or something similar, listed at Banyeres. H & D might know something about them. It looks like they move the stop location for the cam detents half-way between the 2 standard locations. Sort of like a cam-stop half-link.

I've run the dimpled steel plates, OEM fricton plates (2 ea 22201-KY2-000 cork and 4 ea 22201-NN4-B00 paper), and Dexron VI full synthetic with all 6 OEM springs.for 5 years. I've found there's no drag, better shifting, and easy to find neutral. I've also found, in my opinion, the Dexron VI lasts longer than the HTX-740. Maybe because it's formulated to work with wet clutches. But I still change it fairly frequently because it's inexpensive. Did you measure the Apico friction plate thickness? I'm curious about whether or not they're thicker than the OEM friction plates. Another interesting thing seen in other models. The Japanese HRC RTL260F parts list shows the standard (2 ea 22201-KY2-000 cork and 4 ea 22201-NN4-B00 paper) and an alternate clutch pack with all 6 friction plates as 22201-KY2-000 cork. The 300RR uses more cork plates than the 4RT / 4RT260, 4 ea 22201-KY2-000 cork and 2 ea 22201-NN4-B00 paper. I'm thinking of trying the all cork OEM or 4 cork 300RR setup when I replace the plates, keeping the dimpled steel plates.

I've used TwinAir 4RT filters. They are the same as the Jitsie filter, just different colors. Like the Jitsie, they use an integrated coarse, hard foam on the intake side that acts as a backfire screen. So you use it without the steel screen.

On the 4RT, the thermostat isn't a temperature switch, it's a temperature sensor. It's not connected directly to the fan relay. It's connected to the ECU, which uses the coolant temperature data (continuously variable resistance of sensor) along with other sensor input to adjust the fuel injection and ignition timing, as well as tell the fan relay when start the fan. If the sensor is disconnected or circuit is otherwise open, the ECU will put the FI / ignition into a limp mode.

Another suggestion from the image above. You're at the end of snail cam adjustment, and from looking at the tensioner, you may need another notch (but can't tell for sure). No need to remove a link. There's another set of threaded snail cam stop screw holes aft of the current stop. It's under the cam now, but if you loosen things up and rotate the cam you'll see it. Move the stop screws, and you'll get back to the low end of the cam. That's a real bonus getting the Mitani sidestand. Much better than stock.

The P.N. 38771-NLC-000 is the HRC number used when the two-map system was first released. The later versions should work: 2008 RTL260F CD P.N. 38771-NN4-307, 2010 RTL260F CD P.N. 38771-NN4-H00. I've installed the 38771-NN4-307 software on a Windows 7 32-bit computer. It will not install on Windows 7 64-bit computers. If you're using the USB Serial I/F wiring, you can update the Silicon Labs CP210x driver to work with your OS. I've installed the 38771-NN4-H00 software on Windows 7 32-bit & 64-bit computers and a Windows 10 64-bit computer. The manual for this version only shows use with the USB wiring, you can update the Silicon Labs CP210x driver to work with your OS. HRC Japan hasn't updated their compatibility chart online to show the 2010 software, but the 2008 software is backward compatible with TB/ECUs and can support either serial port of USB wiring. I'd think the 2010 software is also fully backward compatible with bikes, but not sure if it supports the old serial port wiring.

Billy, the reed valve, P.N. 18601-MBW-003, is the same on all 4RT models from the original 2005 to present. The same reed valve is used in CRF***R crankcases. I was thinking that's what Rollox's last post was about. The new part that appeared in the 2014 4RT260, when Honda advertised reduction of engine braking, is the small vent jet in the left crankcase half. Look at parts list frame E-11 for 2014+ models compared to earlier models. The newer bikes have an Item # 18 "90901-NN4-D00 ORIFICE #190" that earlier models don't have, and different left crankcase half that accepts it.

I'm referring to the P.N 90901-NN4-D00, ORIFICE #190. It first showed up in the 2010 Japanese RTL260F and then in the 2014 4RT260. Are you looking at the reed valve? The reed valve vents on the downstroke to clear oil from the sump. It's closed on the upstroke, and the ORIFICE #190 relieves some vacuum force on the piston.

There's also a change in the left crankcase half that adds some venting.

Doesn't the CR250 clutch have 8 friction plates rather than the 7 in the 315R clutch pack. That said, the 4-stroke 300RR only uses 6 friction plates. Aside from that, if it's working for you and you're not noticing any increased vibration, no need to change. FWIW, a more common way to reduce drag & stick, and smooth out the clutch action a little, in 315R or 4RT bikes is with dimpled steel plates.

Take a look at page 5 of this manual 2017 Race Replica Kit The HEADLIGHT WIRING WITH SWITCH P.N. 32101-REP-L30 gives you the headlight wiring, headlight switch, and the open connector for your map switch. Is that what you're looking for? If so, should be able to order from an EU or UK Honda parts dealer.

The manual P.N. is in the Parts List: 62NN4JEMH SHOP / OWNER’S MANUAL (ENGLISH) You can download the 2015 Owners Manual (all significant mechanical information same as 2014) and 2014 Parts List PDF files from Montesa Trials Australia.

The 18330-NN4-L70 headpipe is for a 300RR. If the only issue is diameter of headpipe is too large where it fits the silencer, and length looks right, then you might be able to use the 300RR Muffler Packing 18391-MB0-891. That would be if the 18391-MB0-891 packing has the same OD as the 4RIDE 18391-HB7-000 packing, so it fits in your 4RIDE silencer. You may be able to measure at a Honda shop. The 300RR 18391-MB0-891 packing originally came on VF700S in 1984, and has been used on dozens of different models since then, so it's a very common part.

There is a stop setscrew, but it's set and painted from the factory. Don't know how to set it. Do you need to be measuring TPS resistance (How? Undocumented pin on the 32P connector? Access ECU board?) and setting based on some value? Or is it just a stop that's set so the butterfly valve doesn't rest hard against the TB bore? Or is the butterfly valve set for soft closure, and then the ECU is calibrated so the TPS is zeroed? I'd be reluctant to start screwing with that screw without more knowledge. With a used bike, also brings up the question of whether or not the previous owner tried to adjust idle with that screw rather than the air bypass screw. You may want to look and see if the factory paint was broken.

Given the things you've already checked, and that you already corrected the previous owners breather modification, you may want to: 1) Check the throttle cable to make sure it has enough free play per the manual. 2) Adjust the idle up (CCW) a quarter turn. Start, let warm up until fan comes on, blip throttle a few times. The idle should be adjusted after this much warmup. If, when it drops, it then stalls, try again with another quarter turn. See if you can get it to the point where it idles and doesn't stall after the warmup & blipping. Then adjust to proper idle.

Probably not. The transmission is separate on 4RTs and doesn't breath like the crankcase. It just expands/contracts the internal air a little as the motor heats/cools, and the transmission breather prevents +/- pressure on seals. The transmission breather also is routed up high from the gearbox joint, runs back along the side of the frame left of the TB/ECU, and then drops down.

The solution to clutch drag is dimpled steel plates. I use them with the newer OEM friction plates (your 2015 has them) and Dexron VI full synthetic ATF. Very smooth clutch action with that combination, and better shifting (and finding neutral while stopped) than stock with HTX-740.

The transmission breather doesn't go into the storage tank. It just has an open end.

Check the owners manual, pages 2-12 through 2-18 for the standard routing of the crankcase and gearbox breathers. If the crankcase breather ends up going into the airbox port, it may be better to put the catch tank back to reduce the chance of oil going back into the airbox. Some people plug the airbox port and leave a hanging breather end, like the gearbox breather. This guarantees you won't dump oil in the airbox, but on the other hand means you may get dirt / water sucked into the head. Personally, I run mine standard and haven't had any problems. There's also a clear drain cap on the bottom of the airbox. You can look at that and if there's water or oil in the cap, just pull it and let the airbox drain, then put it back on. The tube running from the intake port to the injector assembly is a vacuum hose for the pressure regulator on 2005-2015 bikes. Only thing to do there is make sure it has no leaks.

The FIM (and AMA) has done the same thing with motocross for years. MX2 is 125 2-stroke or 250 4-stroke. MXGP is 250 2-stroke or 450 4-stroke. And 4-stroke Betas can also go to 300cc in Trial2.

Have you ridden one with the newer (-G11) Showa fork? That's what the newer Repsol has, and it's more "lively" than the Showa forks with the older damper assembly.

(1) On the ED and 2ED Street Versions, yes, the relay is in the headlight shell. On the 3ED and 4ED Racing Versions, the relay attaches to the electronics bracket that's above the transmission along with the condensor, regulator, and bank angle sensor. I don't know first-hand because I only own 3ED & 4ED models, but I believe you still have a connector for the relay -- the one that's used on 3ED & 4ED models and forks from the main wiring harness near the big ECU connector. I believe the headlight sub-harness P.N. 32101-NN4-J10 carries this connector forward to the headlight shell, and when the street lighting is removed, most owners use the HL located relay connector and stuff the relay in the headstock area. If you remove the fender and fuel tank, you may be able to trace the two red, blue, and black with blue stripe wires back to the aft end and find a relay connector already in your wiring harness. (2) Usually takes my bikes about 5 to 7 minutes for the fan to come on after a cold start.

Here's a link to the 2017 4RT260 Owners Manual. Look at pages 6-10 and 6-11. On the left side of 6-11, there's a figure showing the connector that the relay plugs into. Note the color markings. The view is of the female connector as you'd see it while plugging in the relay. The text below says it's a 2P Natural, but it's a 4P Black connector on a bike that hasn't had it cut off. Use the hole where the relay assembly tang locks-in for reference. Also, the black wire should have a blue stripe.

Starting with the 2009 models, there's a different silencer endcap for the street versions with a smaller outlet opening. The restrictor inserts at the head and headpipe / silencer junction were last used in 2008.