sportsawyer

I've been running the 5.5" rise Jitsie fatbars on my 2014 4RT260 for about a year, and like them. They feel very close to the 5.5" rise Renthal 7/8" bars I use on my older 4RT, which is what I wanted.

Seemed strange to me too. Also, the idle adjust screw doesn't change the TPS because it doesn't move the butterfly valve. The idle adjust screw changes the opening through an air port that bypasses the butterfly valve. But... it's working, so enjoy the bike.

Hadn't seen the different exhuast outlet. May make it easier to add a spark arrester where they are required. I noticed the photos are also showing the ECU mode switch next to the left grip. Maybe the 2016s are coming standard with a 2-stage (progammable) TB/ECU. Also claiming further reduction in engine braking... #190 orifice to something bigger? I never really noticed much difference due to the earlier change. Footpeg position moved back. Can't tell if this is from different brackets or the new 10mm set-back S3 pegs. Radiator fan cage redesigned so pebbles can drop out easier and not jam fan blade. I had the blade jam once due to a pebble, damaging the fan blade beyond useability (melted plastic around steel hub) and the fan motor got hot enough to discolor. Must be that others had that happen too.

As I recall, the 300cc kits require case boring... I might be wrong. The 280cc kits don't need case modifications, so it's a simple cylinder / piston swap. In addition to guys' comments on cooling and exhaust, you'll want to get a programmable TB/ECU (if you don't already have one) to adjust fueling for the larger displacement. Beyond that, some bore the TB to 30mm for the 300cc setup.

The wire mesh part that fits over the OEM air filter foam. It's P.N. 17213-NN4-000, named "TRAP COMP., FLAME". Jitsie and Twin Air filters have a coarse, hard mesh on the clean-air side that (I believe) is an integrated flame guard.

For the 2014 / 2015 models, the eighth character in VIN is "F" on ED / 2E bikes, "C" on 3E / 4E bikes.

I'm not sure if Bou is using the LH side clutch slave cylinder. Look at the photos from Sheffield. There isn't a good one to see this in the Free Public Photos. But in the TC Supporters Photos look at DSC_0053 & DSC_0055 and you'll see the clutch hose going to the RH side clutch cover the same as production 4RTs. There's still the slave cylinder body on the LH side, but it seems to just be there as a cover on the new case design. I thought I'd seen this in photos from WTC events. As I recall, when Bou and Fuji first appeared with the new engine design, both were using the new LH clutch slave cylinder. But a few events later it looked like Bou's bike had gone back to the old RH actuation while Fuji stuck with the LH actuation. If you see photos of the RH side of Fuji's bike, you'll see a completely different clutch cover from Bou's bike. The different actuation requires a different clutch configuration since it's pushed in opposite directions for disengagement. Then again, maybe my eyes are fooling me. Anyone know for sure?

Don't know if this will help, but the steering head bearings and seals for the 2014 4RTs are the same as an XR400. The Montesa part number for the top seal is 53214-KCY-670, but this has been superceded by 53214-KCY-671 (same part specifications coming from a new supplier). The bottom seal 53214-KA4-701 is also used by many other Honda street and dirt models. I personally don't care for the cheap Chinese aftermarket seal & bearing sets, but I'd guess an XR400 steering head set is readily available. You also might want to check Honda shops for the newer 53214-KCY-671 top seal number.

Shyted, From what you described in post #13 with hot disengagement problems, I'd agree with jrsunt that there's something uniquely wrong with your clutch, or clutch actuation. The only change to the 4RT clutch I'm aware of was the paper friction plates in 2007 (2005-6 used part # 22201-MEL-000, 2007- present use part # 22201-NN4-B00). The two cork friction plates, steel plates, clutch hub, pressure plate, basket, cover & slave cylinder assembly are all the same 2005 - present. There was a change in the master cylinder with the 2014, but those seem to be working alright for the most part. As for the side stand, the aluminum version sold as a Mitani part is excellent -- lighter, stays in place until it's moved (if you don't like the side stand snapping up by itself), supports the bike much better in sand or wind, and the tip is raised so it doesn't snag on rocks. Yes, I think Honda should change to something similar for us riders who don't have lots of handy places to lean our bike, or someone to hold it, while walking sections.

What was the nature of the impact? A very hard, head-on hit of the brake pedal would cause bending rotation that would result in tension in that area (backside of brake boss). If that's the case, it could be just crazing of the brittle anodized surface, like others have already brought up. Here's a link to an explanation of anodized surface crazing: http://www.aacron.com/docs/Crazing%20Caused%20By%20Bending%20and%20Forming%20Operations.pdf I've seen a lot of crazing radiating from spoke holes in hard-anodized bicycle rims. The rims lasted and cracks didn't start (or go to failure / nipple pull-through) in the aluminum rim. There still could be underlying cracks starting in the alumimum frame, so keep an eye on it as suggested.

Update on the setup I'm using: Dimpled steel plate set (available from Apico or Jitsie retailers like BVM Moto or Splat Shop) and the OEM friction plates -- 2 each 22201-KY2-000 cork and 4 each 22201-NN4-B00 new type paper -- with Valvoline Dexron VI full synthetic ATF. I first installed the above in my 2005 4RT in May, and it worked so well I changed my 2014 4RT260 to this setup when I ran out of ELF HTX-740 later in May. I was mainly driven by the fact that HTX-740 had become unavailable in North America and only thicker oils were available. But the above dimpled-steel setup worked better for me all-around -- smoother and longer engagement, no drag, no stick after sitting a few weeks or more, easier shifting, easy to find neutral, much less expensive for oil changes, and oil that's readily available from local auto parts stores. To give an example of the elimination of drag and stick, as a test I recently started my 2005 4RT after having it sit unused for a month, cold and in first gear, on the 2nd kick. It didn't walk away with clutch stick or drag, just sat there idling. After a little time, with the bike still stationary, I shifted it into neutral with ease.

Silkolene Pro-4 SX is full-synthetic and available through various US sources in 15W-50 or 10W-40. I use the 15W-50 in my KTM 450. What do you dislike about your clutch action? Too fast, too slow, uneven, or something else?

Agree with shedracer... that was my experience with the Showa suspension on my 2014. I'd reduced damping 4-5 clicks on both ends after my first practice / dial-in session. After several practice sessions I found the suspension getting too bouncy and had to turn damping back up. Feels great now. Just give it some practice time and maybe reduce damping until things loosen up.

The photos I've seen only show the top side, and I haven't seen one in real life. So don't know if there are any separators. Either way I'd expect they could cause rub marks, and if it was an issue you could use some tape on the tank. I know it's not the goal of the original post, but I've looked at these covers as more a shroud for an already damaged or otherwise uglified but usable tank. More like the covers for Mitani SP3 type flat tanks, which don't have a nice finish on the aluminum (like the SP1 type flat tanks) and use the cover as a cosmetic layer.

A few days ago I wrote: "Mitani is, or will be, making a cover. But I haven't seen them listed yet by UK or EU Mitani sources." Banyeres has the 2014 model year tank covers in stock now, in either black or silver. Just listed them today. FWIW, I wouldn't think the earlier tank cover shape would fit very well... it wouldn't match the tank / fender junction and wouldn't fit the tank contour. Not sure about the gas cap hole, but it might be located differently too.

Mitani is, or will be, making a cover. But I haven't seen them listed yet by UK or EU Mitani sources.

As ELF HTX740 became unavailable in the USA, I was very interested in trying the GRO Gear Extrem 75 because of the close viscosity match to the ELF oil. But there's no current USA importer of GRO oil. I also checked Canada for both, no luck. And no dealers seemed particulary interested in getting either the ELF or GRO. Having it sent via air from the UK also seems to be a problem, and none of the dealers I checked with would send to the USA. So I started looking for something else. Wanting to get the closest viscosity (to HTX740) of available oils, I tried the Valvoline Dexron VI full synthetic mentioned above. It worked well when hot, but was sometimes a little sticky and had more drag when cooler. I also started getting some strange engagement... but I think that was mainly due to a well-worn Mitani clutch in my 2005 4RT. So I went with the Jitsie dimpled steel plate set I had laying around and new OEM clutch friction plates -- 2 each 22201-KY2-000 cork and 4 each 22201-NN4-B00 new type paper -- with the Valvoline Dexron VI. This has suited me very well. No sticking or drag, with very smooth and predictable engagement. I just did the first change on my MRT260, and that's about the end of HTX740 I had. So I'll probably change to dimpled steels with Dexron VI on that bike with the next change. The Valvoline Dexron VI is readily available for only about $8 / quart in the USA at O'Reilly stores.

As I recall, Mike Carlton can replace the fuel pump if you send the bad fuel pump assembly for a lot less than replacing the whole assembly. You can find his contact information on the Central Arizona Trials website under "CAT Officers."

Are you sure you have the rpm counter set for a single-cylinder 4-stroke? Your 1100 rpm sounds like it's over 2000 rpm, and sounds faster than my bike at idle. Mine is at the manual specified 1800 rpm, done using a Pulse PET-1100 set for a 4-stroke thumper.

The Race Replica also has Michelin tires, Standard has Dunlops.

Looks like the rules require at least 5 riders in a class. So a lot of the SR age classes and other support classes may not have enough riders. Maybe Honda could make an exception for trials.

You could pull the clutch first (just through the clutch cover), and get a view of the right side of the gearshift spindle and shifting mechanism. Could be something there got bent or otherwise messed-up. You'll need to eventually remove the clutch anyway if you need to dig in to the center cases, so it's not a lost effort. But may save you from removing the engine, splitting the cases, and buying all the gaskets you'd need if that's done. Check the owners manual page 4-44. Good luck. Hope you don't need to split the cases.

Here's a photo of my stock 2005 4RT clutch plates. Yours looks like stock, but you be the judge. Note that's been out of the bike for a while, so its dryness may change the appearance a little. I'd recommend checking with Adrian at LewisportUSA about your problem, he may have some insight.

I have a Mitani clutch, and it has 3 different types of friction plates (2 of each type). There may be other Mitani clutches with 2 types. The stock clutch has 2 types (2 each PN 22201-KY2-000 cork in positions 1 & 6, and 4 each 22201-MEL-000 paper in positions 2-5). Your picture looks like the stock clutch. If you didn't get the service/parts manual, there are 2005 and 2009 parts manuals (in PDF) on-line at the LewisportUSA website. The engine oil is separate from transmission oil. I only bring it up because you only mentioned the engine oil. I've been using the recommended transmission oil -- ELF HTX740. It's pricey but works well. Not sure about your problem, but you might try some fresh HTX740 and see how your clutch works. The HTX740 is clear to light amber in color, mine usually comes out pretty clean after 6 months. FWIW, I use the same engine oil as you're using.

According to the , it'd be choice 2 -- only one point. See the linked video starting at about 2:50.