Nigelpugh Posted September 3, 2023 Report Share Posted September 3, 2023 Hi guys, Sadly we has a fire at our house last week and my Montesa 4RT suffered some fire, smoke and water damage. It’s not insured regrettably so I have to see if I can get it up and running again. The heat and fire damage seems to have affected a few plastics like the rear mudguard and also killed the rear tyre too. However at this point I also can’t get it to start at all, so I’ve been trying to work out what’s wrong in a step by step fault finding basis. The first thing we noticed was that the throttle cable was stiff and stuck and not returning to its home position. We have now removed that and will order a new one. The bike is still not starting though, so we pulled the plug out and it’s not sparking at all on kick over. We did notice that the jitsie magnetic kill pull looked like the cables might have melted., so tried unplugging that and shorting the ignition feed. Still no spark. So what’s the best next steps to fault find why we don’t have a spark. Thanks for any tips or pointers! Quote Link to comment Share on other sites More sharing options...
jonnyc21 Posted September 3, 2023 Report Share Posted September 3, 2023 Considering it was hot enough to toast a tire and fender, I would check for melted wires shorting on the frame or other chassis component first thing if you don't see spark. Possible it could have caused an issue by melting something inside the ECU on the throttle body as well, however wire harness issues would be my first check. Good luck. 1 1 Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 4, 2023 Author Report Share Posted September 4, 2023 (edited) 11 hours ago, jonnyc21 said: Considering it was hot enough to toast a tire and fender, I would check for melted wires shorting on the frame or other chassis component first thing if you don't see spark. Possible it could have caused an issue by melting something inside the ECU on the throttle body as well, however wire harness issues would be my first check. Good luck. Thanks I will have a good luck at the other wires on the rest of the loom today. It looks like we are still getting power, because when we kick the engine over the front LED lights up for a brief amount of time. I assume it more common for the low voltage cables to have issues rather than the high voltage output side of the coil pack? Edited September 4, 2023 by Nigelpugh Spelling. Quote Link to comment Share on other sites More sharing options...
lemur Posted September 4, 2023 Report Share Posted September 4, 2023 Does the tip over sensor appear damaged? It's located back there close to the rear fender and tire, plus it can definitely stop the engine from running. Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 4, 2023 Author Report Share Posted September 4, 2023 19 hours ago, Nigelpugh said: Hi guys, Sadly we has a fire at our house last week and my Montesa 4RT suffered some fire, smoke and water damage. It’s not insured regrettably so I have to see if I can get it up and running again. The heat and fire damage seems to have affected a few plastics like the rear mudguard and also killed the rear tyre too. However at this point I also can’t get it to start at all, so I’ve been trying to work out what’s wrong in a step by step fault finding basis. The first thing we noticed was that the throttle cable was stiff and stuck and not returning to its home position. We have now removed that and will order a new one. The bike is still not starting though, so we pulled the plug out and it’s not sparking at all on kick over. We did notice that the jitsie magnetic kill pull looked like the cables might have melted., so tried unplugging that and shorting the ignition feed. Still no spark. So what’s the best next steps to fault find why we don’t have a spark. Thanks for any tips or pointers! Update and thanks for the response to others too. It was indeed the melted cables on the jitsie magnetic cut out, it looked like one of them was shorting to the handlebar hence making the ignition cut out. Disconnected it and removed it completely and when we put the plug back in it fired up straight away. We will get the cable ordered now and start on the rest of the mostly cosmetic damage to get it back to normal. Thanks again. 2 Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 4, 2023 Author Report Share Posted September 4, 2023 1 hour ago, lemur said: Does the tip over sensor appear damaged? It's located back there close to the rear fender and tire, plus it can definitely stop the engine from running. The bank angle thingy? Nope that was one of the first things I looked at, and it seems fine. Anyway as posted it was indeed the kill switch , and it’s running again now! 2 Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 6, 2023 Author Report Share Posted September 6, 2023 On 9/3/2023 at 5:22 PM, Nigelpugh said: Hi guys, Sadly we has a fire at our house last week and my Montesa 4RT suffered some fire, smoke and water damage. It’s not insured regrettably so I have to see if I can get it up and running again. The heat and fire damage seems to have affected a few plastics like the rear mudguard and also killed the rear tyre too. However at this point I also can’t get it to start at all, so I’ve been trying to work out what’s wrong in a step by step fault finding basis. The first thing we noticed was that the throttle cable was stiff and stuck and not returning to its home position. We have now removed that and will order a new one. The bike is still not starting though, so we pulled the plug out and it’s not sparking at all on kick over. We did notice that the jitsie magnetic kill pull looked like the cables might have melted., so tried unplugging that and shorting the ignition feed. Still no spark. So what’s the best next steps to fault find why we don’t have a spark. Thanks for any tips or pointers! Update and thanks for the response to others too. It was indeed the melted cables on the jitsie magnetic cut out, it looked like one of them was shorting to the handlebar hence making the ignition cut out. Disconnected it and removed it completely and when we put the plug back in it fired up straight away. We will get the cable ordered now and start on the rest of the mostly cosmetic damage to get it back to normal. Thanks again. So I’ve ordered a new rear tyre, a rear mudguard, a new kill switch and a new throttle cable, they should be delivered Friday, so I can fit most bits at the weekend. I will post some pictures of rhe work as I do each section. 1 Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 9, 2023 Author Report Share Posted September 9, 2023 My new parts arrived yesterday, so I will make a start on fitting them today. I still think the hardest part to install will be the throttle cable. I have still not managed to remove the old damaged one, as it looks like I will either have to twist or remove the whole of the EFI throttle body to remove and refit the new cable, Any tips on removing and replacing the throttle cable guys? 2 Quote Link to comment Share on other sites More sharing options...
jrsunt Posted September 10, 2023 Report Share Posted September 10, 2023 Throttle cable replacement is best with the throttle body off the bike. Since you have a lot of the bike apart, you’re nearly there. Remove the silencer mounting bolt from the air box and the 2x 10mm nuts and 10mm bolt the air box will be almost free. The petrol tank will need lifting too. There is a lot of rubber pipe work running from the cylinder head breather to the air box, all this can be removed. Just blank the hole in the air box and use some of the grey pipe to make a new head breather that runs down the side of the radiator on to the sump guard. A little weight saved and much neater under the petrol tank. Make a note of where the lock nut is on the cable, undo the cable from the throttle body by turning the body. Fit the new cable to the body and tighten the lock nut in the same position as the old one. It takes a little patience in getting the new cable routed under the tank so it does not pull the cable when the steering is turned, particularly to the right 2 Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 12, 2023 Author Report Share Posted September 12, 2023 On 9/10/2023 at 2:23 PM, jrsunt said: Throttle cable replacement is best with the throttle body off the bike. Since you have a lot of the bike apart, you’re nearly there. Remove the silencer mounting bolt from the air box and the 2x 10mm nuts and 10mm bolt the air box will be almost free. The petrol tank will need lifting too. There is a lot of rubber pipe work running from the cylinder head breather to the air box, all this can be removed. Just blank the hole in the air box and use some of the grey pipe to make a new head breather that runs down the side of the radiator on to the sump guard. A little weight saved and much neater under the petrol tank. Make a note of where the lock nut is on the cable, undo the cable from the throttle body by turning the body. Fit the new cable to the body and tighten the lock nut in the same position as the old one. It takes a little patience in getting the new cable routed under the tank so it does not pull the cable when the steering is turned, particularly to the right Thanks for that info bud, really helpful. I didn’t get time to do any work on it at the weekend, might try later today. Thanks again for the tips. Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 14, 2023 Author Report Share Posted September 14, 2023 On 9/12/2023 at 10:32 AM, Nigelpugh said: Thanks for that info bud, really helpful. I didn’t get time to do any work on it at the weekend, might try later today. Thanks again for the tips. I’ve made a start on it today. As you said much easier with the throttle body off the bike. Found lots of dirt in hidden areas so decided to clean the throttle body and air box fully whilst off the bike. 1 Quote Link to comment Share on other sites More sharing options...
majesty Posted September 14, 2023 Report Share Posted September 14, 2023 Nice job Nigel. Well done. 1 Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 15, 2023 Author Report Share Posted September 15, 2023 17 hours ago, majesty said: Nice job Nigel. Well done. Cheers Bud! I did mostly finish all the jobs yesterday, just need to fit the new rear tyre next. Seems to be running very sweetly now to. I suspect that the throttle cable was not that good for quite some time before the fire too. 2 Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted September 15, 2023 Author Report Share Posted September 15, 2023 I also fitted the new rear secondary mud guards too. Almost threw the old one away before removing the little alloy ring inserts first! 2 Quote Link to comment Share on other sites More sharing options...
Nigelpugh Posted March 4 Author Report Share Posted March 4 6 minutes ago, gontierbat said: sounds like you're taking a methodical approach to troubleshooting the issues with your bike, starting with addressing the visible damage to the plastics and the rear tire ordering a new throttle cable is a good call, as a stiff and stuck cable could definitely cause starting problems. Thanks for the comments bud. Looks like I forgot to update the current status. It’s pretty much complete now. Let me dig out the latest pictures. Quote Link to comment Share on other sites More sharing options...
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