ludde

Added some more info and updated some of the pictures.

That is a tricky question. It looks like your throttle body is a Japanese one from 2007. I think those were 2 map bodies. Was your bike delivered with that throttle body?

MCU Innovations free software worked for me, but only for reading bins. I bought a flash license to be able to write to the ECU. After that I have written to ECUs several times. I have bricked two ECUs because of stupid mistakes from my side. I have tried to get them to work again but no luck so far. Which ECUs have you read?

Sorry, I missed that you replied. I am using HondaECU by MCU Innovations. It has worked well for me. I will do some testing this weekend to see if can confirm more stuff but it is difficult since it is subjective what I can feel the changes do. I would have loved to be able to a proper Dyno test with external sensor to confirm the maps. Have you built your own xdf file or did you buy it?

Added some more info on the different softwares to the original post.

I haven't written anything here in years but now I have information that I think some will be interested in. This will be quite technical so bear with me. I am writing this from the standpoint that you know how the use the HRC software to change the mapping in the ECU. More info to come. Background Almost a year ago now I came across some software developed to flash the ECU of different Honda motorcycles. Being an engineer I started to wonder if it would be possible to use on the 4rt. I have always been annoyed that the HRC software only lets you modify fuel and spark advance in relation to some maps that are unknown. After some research I found that the flash software monitors if the ignition (12V) is on to know if the ECU is alive or not. Well, the 4rt does not have a battery and the red 4P connector in the harness which you use to communicate with the ECU does not have any 12V or ground wires. So an adapter harness needed to be created. The connectors are Sumitomo HM090 series. I used the 12V and ground from the black 2P connectors the you use to power the ECU and then made a harness with a 4P connector which looks like this. It worked! I was able to read a 32kB bin file from the ECU. Having had 4rts since they were launched I had a couple of throttle bodies laying around. So a total of 5 bins were read. Now the big job of trying to interpret the hex code started. I won't bore you with all the details so here is what has been found out so far. Information ECUs read (as of now) 16400-NN4-XXX G11, H01, J11, L11, L72, M11, M62, M71, P01, P71 There are 2 main softwares used since 2009 I think, NN4D101 and NN4G202. Non of the software send any diagnostic information via the K-line sadly enough. NN4D101: Switchable between MAP1 and MAP2 on the handlebar. (3ED/4ED) HRC programmable 1 set of RPM, IAP and TPS axis. 2 sets of maps for Fuel and Spark advance. NN4G202: Street legal version (ED/2ED) NOT HRC programmable 2 set of RPM, IAP and TPS axis. 2 sets of maps for Fuel and Spark advance. Fuel 2 maps, one based on RPM and IAP (inlet air pressure), one based on RPM and TPS (throttle position sensor). No clue yet to what the numbers mean other than higher number is more fuel. How they work in relation to each other I am not sure of right now. WIP I think there is also some kind of acceleration enrichment. WIP Spark advance 1 map, based on RPM and TPS. The numbers are still a bit of a guess but they seems to be about right. There is also a transient spark advance which adds or subtracts from the main map. This is active when you snap the throttle and the engine is not able to keep up with what you are demanding. Other functions RPM Limiter, looks like 3 different limiters. Only one has been confirmed. The different softwares G11 2009-2012 Montesa ED/2ED This is the oldest software I have right now. Is very similar to H01 but has less fuel since the Montesa still was 250cc. H01 2010 HRC RTL260F This software has two very different maps. Map 1 is you standard map providing as much power as possible. Map 2 is a very soft map with lowered spark advance and a low transient spark as well. This takes away all the punch the engine has but is great in slippery conditions. You have to rev the engine if you need some power but the traction is great. J11 2014 Montesa 260cc ED/2ED Very similar to the H01 softwares Map 1 with small changes to fuel and ignition. Probably due the difference in exhaust muffler between the Honda RTL and the Montesa. L11 2016 Montesa 260cc ED/2ED For 2016 a new fuel pump was fitted which changed the fuel and ignition maps a lot. L72 2016 Montesa 300RR 4ED The 2016 300RR has a 2 ring piston compared to the later 300RR which has a three ring piston (the same as the 260 but bigger). Therefore this software has a unique settings which is different to both L11 and M71. Map1 has lower spark advance on small throttle openings making it softer than map2. Map2 is the power map. The 2016 300RR I have seen also had a HRC setting which adds even more spark advance to map2. M11 2017-2018 Montesa 260cc ED/2ED Same as L11 except for changes to the homologated map (street legal). Probably due to the change in rear sprocket from 36 to 41 teeth. M62 2017-2018 Montesa 300RR 2ED Same as M11 but has more fuel in the TPS map from 50% and up. M71 2017-2018 Montesa 300RR 4ED Map 1 is the same as M62 Map 2 has the same fuel as Map 1 but a little higher spark advance to get more power from the engine. My PTB had a setting in the HRC program which made Map 1 softer increasing the difference between the maps. P01 2020-2022 RTL300R Uses the same settings as the P71. P61 2020-2022 Montesa 301RR ED/2ED This software has a strange mix between the M62 software and the P71 software. I have not tested it so not sure if it makes any difference. P71 2020-2022 Montesa 301RR 3ED/4ED Interestingly the 301RR software is much more similar to the H01 software than the M71 form the 300RR. I am wondering if HRC made the settings for the 301RR but Montesa in Spain did the 300RR? Map 1 is the power map with a quite aggressive transient spark map which adds quite a lot of advance. Map 2 is the softer map with less fuel, lower spark advance and lower transient spark map as well, compared to Map 1.

We got one 4RT 260 here in Sweden that I test rode last weekend. The new engine is really nice. Little softer on low revs but alot more punch on mid and high revs. The engine feels more lively and smoother in its power delivery. That camshaft together with the changed fuel injection map does make a big difference. The changed engine brake was only noticable to me on low revs when you open and close the throttle. Now when you close the throttle the engine does not brake as hard as before. This give a smoother feel on low revs. The new suspension do make the bike feel alot lighter and nimble. One guy that test rode the new Montesa rides a Sherco normally and he thought the Montesa ha a better setup even though it is the same suspension compnents on the Sherco and the new Montesa. The suspension is quicker than before but still has that smooth soft feeling a Montesa always have. However, I have been spoiled by riding with Showa suspension for the last eight years. I did't get the same confidence with the new suspension and to me it felt a little unstable. It is probably only a setup issue. Bottom line is: TRY the standard bike BEFORE you discard it as the cheap bike no one wants. It will surprise you.

It is actually cable operated but there is no conduit on the cable. It looks like this: I can imagine the frustration of Birketts because the alignment is one of the reasons I'm converting it back to drum brakes. Every time I take the wheels of I have to get everything lined up perfectly otherwise the brakes will squeak or not work properly. The rear swing arm is original as far as I can tell. There is no marks from any cutting and re-welding apart from just in front of the brake caliper. Maybe that bit has been changed to accommodate the caliper.

Hello It has been a while since I have posted here but now I need some help from the RTL owners out there. I have a -87 RTL which was converted to disc brakes by Nigel Birkett at the previous owners request. The previous owner sold the drum brake wheels which meant I couldn't restore the bike to it's original state. Until now. A month ago I received two drum brake wheels from Japan. The rims are a bit corroded but the hubs are mint which is the most important. Anyway, I have all the parts I need to fit the drum brakes except from the front and rear brake cables. Venhill has all the cables for the RTL except for the rear cable. Does anyone know where I can find one? Otherwise I think I can use the rear brake cable form a 1980s CR80 which looks the same but is too long. What's the correct length for the cable on a RTL? Also if anyone has a photo of the brake pedal pivot I would appreciate it. I need to fabricate that as well. I know use you can't just ask a lot questions without posting pictures of the bike in question This is how it looks today. A photo on the same bike from 1988 When I ordered the wheels form Japan I also got me one of these just for fun

No there almost no one riding around Lund that I know of. A couple of years back there was a small gang riding Pre-65 bikes but I don't think they are active any more. There isn't alot of forrests around Lund and the terrain is quite flat. As Carl said around Gothenburg there is plenty of club and areas to ride in but that's 160 miles north of Lund.

Yes

Correct, you can't judge the 09 by the older models. It's a different bike, more agile and easier to ride. My old 06 repsol had 280 kit, mitani titanium exhaust system, modified linkage plates, and changed gearing. After all these changes it felt really good to ride. Until I tested a standard 09, after that I didn't my want my old bike anymore, the 09 so much more comfortable to ride. My new 10 (09 registered as a 10) is as original as can be. The only changes I have done is to increase spring pre-tension half a turn at the front and one turn at the rear. Rear damping set to 4-5 clicks in (depending on conditions). That it! I just wish Montesa had released the 09 back in 05. So hurry up and buy one in case they would disappear

Could be that they are just waiting for the stocks of finished bikes to go down and then resume when the demand grows. Just pushing the cost of production forwards as long as they can, hoping that people will start buying cars and bikes again.

From what I heard from our importer in Sweden is that the bikes sold in 2010 will be 2009 bikes, same plastics and everything. If that is because they are shutting down or developing a new bike for 2011 I don't know. I hope it's the latter