Japzap643 Posted August 4, 2022 Report Share Posted August 4, 2022 (edited) I’ve got a new, 1.5 hour Montesa 301. Bike has always been incredibly easy to start. 1-2 lazy kicks and it runs. I had the bike sat for some time running VP Trials fuel, no ethanol. Now coming back to use it, bike goes to start but barley idles on the first kick where it now struggles to stay running. It then takes many kicks before you can get it up and running again, once you get it going you need to crack the throttle to keep the rpm elevated slightly and then from there it runs flawlessly. Is it possible that I may need to swap a spark plug? Not sure what’s causing this with less than 2 hours on the bike. Edited August 4, 2022 by Japzap643 1 Quote Link to comment Share on other sites More sharing options...
lineaway Posted August 4, 2022 Report Share Posted August 4, 2022 Did you ever adjust the idle? 1 Quote Link to comment Share on other sites More sharing options...
lineaway Posted August 4, 2022 Report Share Posted August 4, 2022 Go to page 3-8 in your manual and turn the idle adjustment screw 1 full turn counterclockwise. You have to remove the seat to get to it. 1 Quote Link to comment Share on other sites More sharing options...
Japzap643 Posted August 4, 2022 Author Report Share Posted August 4, 2022 I will check idle. Thus far I have no touched it Quote Link to comment Share on other sites More sharing options...
lineaway Posted August 4, 2022 Report Share Posted August 4, 2022 2 Quote Link to comment Share on other sites More sharing options...
Japzap643 Posted August 11, 2022 Author Report Share Posted August 11, 2022 What is the best practice to check idle? Dealer tool? How are you getting accurate RPM? Quote Link to comment Share on other sites More sharing options...
jonnyc21 Posted August 13, 2022 Report Share Posted August 13, 2022 (edited) On 8/11/2022 at 12:45 PM, Japzap643 said: What is the best practice to check idle? Dealer tool? How are you getting accurate RPM? I got an hour meter with tachometer integrated. No affiliation just liked the mount and meter. Meter: https://www.hardlineproducts.com/product/hourtach-meter/ Mount: https://www.hardlineproducts.com/product/hour-meter-instrument-style-mount/ Edited August 13, 2022 by jonnyc21 Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 1, 2022 Report Share Posted September 1, 2022 I’ve just picked up a new to me Montesa 4RT. At first mine did exactly the same as your description, so I thought something was not right and rang the dealer. It turns out due to the fuel injection system, you must not even touch the throttle prior to starting it, my dealer even said don’t even put your had on the throttle grip, which I must have done, as now it starts first time. The process in the video from the Spanish guy is pretty much spot on. Out of interest what’s the advantage of using the special fuel you mention? I had not heard of it before. Hope this helps in a small way! Quote Link to comment Share on other sites More sharing options...
jonnyc21 Posted September 2, 2022 Report Share Posted September 2, 2022 22 hours ago, Nigelpugh said: I’ve just picked up a new to me Montesa 4RT. At first mine did exactly the same as your description, so I thought something was not right and rang the dealer. It turns out due to the fuel injection system, you must not even touch the throttle prior to starting it, my dealer even said don’t even put your had on the throttle grip, which I must have done, as now it starts first time. The process in the video from the Spanish guy is pretty much spot on. Out of interest what’s the advantage of using the special fuel you mention? I had not heard of it before. Hope this helps in a small way! VP fuel is a racing fuel so will have no ethanol in it and is often a higher octane level. Most of the people I know that get VP are after the no ethanol because they don't have a non-ethanol option at a standard pump station. Some feel there bikes run better on the VP. Most of the people I know that like the VP ride 2T bikes, and a few people I know have tried it in their 4RT's and had issues. Also, some will mix standard octane non-ethanal with the VP and really like that. In the end it can make a difference depending on bike, conditions, modifications, etc. and preference in most cases. 1 Quote Link to comment Share on other sites More sharing options...
IBA4rt Posted October 27 Report Share Posted October 27 I return to the topic since I have a similar problem, the bike is new, 301 model 2024, delimited with a race kit with exhaust without catalyst and P71 ecu. The bike starts more or less well when cold and hot (first or second kick) but it has a hard time maintaining the idle speed, especially when cold, with irregular idling and backfiring. The operation is correct, the motorcycle runs well but when you release the gas the idle is erratic with some backfiring. It smells a lot like gasoline. I have removed the spark plug in the state that I provide in the image. totally black. I have regulated the idle speed and it regulates it regularly but it fluctuates erratically with some backfires and desynchronization of the idle speed regime. I have changed to 98 gasoline with 5 percent ethanol, there is no other in my area. any ideas? Quote Link to comment Share on other sites More sharing options...
lineaway Posted October 27 Report Share Posted October 27 (edited) You really need a tach on the 301. I will let mine idle until it reaches above 2000 rpm. If you run the idle low it will run terrible. Follow the above video and reset the ECU. I went through that same issue. You just have to get used to this is a high idle bike. Always when starting, never touch the throttle and let the bike idle for awhile without blipping the throttle. I mean EVERY TIME. Once cold almost a minute, when hot at least 20-30 seconds. Edited October 27 by lineaway 1 Quote Link to comment Share on other sites More sharing options...
IBA4rt Posted October 27 Report Share Posted October 27 thanks for responding. I had read that the optimal idle speed was 1800 rpm. Right now I don't have a tachograph but I estimate that it will run around 1800 rpm but it works irregularly, on the first burst of gas it smells like gasoline and after 2 hours of use this is what the spark plug looks like. I have been told that some of the 2022 and 2023 models came with a fuel pump problem that prevented them from starting hot. There is even a scam about it. Mine starts well when cold and hot, my problem is unstable idle and backfires more when it's cold than when it's hot. I understand that your motorcycle, with the idle speed above 2000 rpm, has a stable idle speed without failures? With those revolutions don't you have the electric fan running all the time? Mine is another thing that I detect, that the fan is activated practically all the time and has very long cycles. Quote Link to comment Share on other sites More sharing options...
lineaway Posted October 27 Report Share Posted October 27 (edited) I bought my tach, before my bike showed up. After 8 months after a bad weekend of the bike running like crap, I finally installed the tach. I have not had a problem since. My idle is set above 1800 when it starts and I do not touch the throttle until after it reaches above 2000. I would replace the plug. I also had to replace the plug cap as it was bad also. Yes we have had several bikes need a new fuel pump. All `22/`23 models, Good luck. Until you reset the ECU it will continue to run bad. Edited October 27 by lineaway 1 Quote Link to comment Share on other sites More sharing options...
IBA4rt Posted October 27 Report Share Posted October 27 thank you very much again. I'm going to do what you tell me. I will keep you informed. thank you very much again. Quote Link to comment Share on other sites More sharing options...
lemur Posted October 27 Report Share Posted October 27 I can't even imagine how a 4RT engine could be making that much carbon, unless the sump is pumping engine oil into the intake or the air filter is over saturated with filter oil and it's sucking that into the intake, or an intake valve guide compromised. Does your engine eat oil? Quote Link to comment Share on other sites More sharing options...
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