handmadematt

So, I've been into classic green laning for a while on my Royal Enfield and as some of you know I've only recently bought a Montesa Cota 247 classic trials bike, I've taken it down some lanes but am yet to go to a trial with it. I will be going in a few weeks. So, I was wondering if for now my existing gear is OK? I have a budget open face road helmet that I use down the lanes, it's similar to this one: http://www.ebay.co.uk/itm/VIPER-RS-04-PLAIN-OPEN-FACE-MOTORCYCLE-MOTORBIKE-SCOOTER-MOPED-CITY-CRASH-HELMET-/400320783636?pt=UK_Motorcycle_Helmets&var=670043912026&hash=item5d34fa6514 And I have some old black road motorcycle boots that I wear on dryer gentler lanes and if it's wet and muddy I wear some walking boots with gaiters. I don't mind spending some cash on some new boots if I have to... I was thinking about some Wulfsport ones (linked below,) I like the look of the brown leather: http://www.ebay.co.uk/itm/370649573809?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649 Cheers.

My two pence worth: I had £1300 that was destined for my ISA savings account but instead of giving it to the hungry greedy bankers I decided to "invest" it in something that I was going to enjoy. Old twin shocks certainly hold their value at least and if I do end up owning it for 15 or 20 years I could even make money on it. When I was shopping around for a twin shock I found that there were many more TY's available and that they were cheaper (in general.) Right now on eBay there's a chap in Yorkshire I think with ten TY's ranging from £600 - £1,200 depending on the condition. Equally there are much fewer Montesa's on the market right now, some going for up to £2,000 or more. The TY's do seem to have a reputation as a more capable "modern" bike, I've met people who aren't into Jap bikes but think they're great. The Montesa's seem to be more collectable in other ways though, like it's already been said here people like them outside of the trials scene. Whatever you get will be the right thing though... That's the way it seems to work! Let us know how you get on.

I don't think there is a grounding issue. When I fitted the new HT coil the engine started nicely, to confirm that it wasn't just coincidence I then swapped it back for the old one and I couldn't start the bike, re-fitted the new one and then hey presto. An interesting thing came up in regards to the ground though. When I was looking in the magneto case behind the flywheel checking if everything was OK I discovered that one of the magneto coils (of which there are three) had it's earth (green wire) cut and hanging loose. The other end of the green wire that ran all the way up to the HT coil was earthed to the engine case behind the flywheel here. I traced this up to the HT coil and it was earthed to the HT coil mounting point... So the previous owner has had the HT coil earthed twice, once here with this green wire and again with an addition of a black wire that runs down the inside of the frame (inside the riders leg) and bolts to the engine case above the drive sprocket. I confirmed this by disconnecting the black wire and I still got a spark. So, having discovered this I had previously thought.. "Ah, with one magneto coil out of service maybe that is my problem." So I had already re-connected that to the same earth that the green wire was already on inside the magneto case. It did not solve my problem unfortunately. Maybe this "third" magneto coil is only for auxiliary lighting or something? Is it not part of the ignition? The bike clearly ran before without it... Unless that's what caused the HT coil to fail? A contestant under powering from the magneto? (Seems unlikely to me.) Anyway, it's all working now. Cheers.

SOLVED. Thank you everyone, really - So much thanks! It was the coil. I changed it for a new one and she literally starts first kick in any situation... An absolute joy. I appreciate that many of you said this straight away and I've investigated all sorts of other avenues but there is nothing lost, it's been an important journey for me and has resulted in me being fully acquainted with the bike, inside and out... She feels like an old friend already. What a valuable resource this forum is, thanks for making it what it is. Speak soon. Matt

What do you mean? So had I.

I managed to snap this one for you mate. She's a bit dirty around the engine but that's what they're made for! This is a great idea. (Today I couldn't even start the engine besides one kick where she splutter for ten seconds before dropping out and dying.) So, I connected up my timing strobe with the plug out but earthed with a piece of wire. I got multiple fast flashes every time when spinning the engine over by hand. (Which was relatively easy with the plug out.) When the plug was back in though the strobe would only flash briefly once every other kick or so. So I think some of you may be right about the plug failing inside the cylinder. In the morning I'm going to repeat my strobe experiment and if I get the same results I'm going to remove the carb and repeat. If I can confirm that the spark is failing inside the cylinder even with the carb disconnected then it is the compression that's snubbing out a weak spark. If by some chance the plug does fire properly inside the cylinder without the carb then I can investigate a potential problem with fuelling/ flooding and fouling of the plug. It's fascinating because the motorcycle works by running multiple independent systems which must all harmonise and work together to produce a functioning engine. Ignition, air and fuel for example. In my case each one of these systems is working correctly when independently inspected. They are all observed to function but that synergy is not happening. When combined, these systems are not harmonising to produce the desired result. A bit of mystery and a bit of fun in the workshop. I guess this is what I signed up for and this is what I get. ...If the plug fails tomorrow under compression with the carb off then I'll finally try a new coil. Here's hoping. Thanks again.

Hi Terry mate, thanks for the reply. They are great bikes hey!? I think you're right. I'm going to get one when the supplier re-opens. That's a good idea. It might help with diagnosis. Cheers bud. I'll post some up later today or tomorrow. Thanks again.

I don't know how old it is exactly but the previous owner had fitted it and he owned the bike for six years. It all looks in good condition though with certainly no damage. Interesting, although when I select model and make of my bike, the carb it recommends is listed as a four stroke. I'd prefer to identify the problem with the existing carb and fix it to be honest. It'll be much cheaper obviously. Thanks again for everyones input.

You reckon? Resulting in a rich mixture meaning an easily flooding engine? That's certainly what it feels like to me. Since opening and closing the carb so many times the gasket's given out and needs replacing. The bowl does leak a bit now now when tipped up. It's not overflowing though because the over flow pipe has never exhibited a flow. This is certainly worth investigating. It's the route I've felt to be a problem but so far I've been convinced on here to focus on the electrics. We'll see.

Elaboration would be appreciated. Many thanks.

That's very kind of you. I'm about 50mins from you cose to Guildford. I have already bought one though and done the job. I still have starting problems unfortunately.

Happy Christmas. Would that also work if I just took the plug out and spun it over? (I've not noticed any mess when I've done this to check the spark (which has been many many times now! Ha.) I guess my reluctance is that it just doesn't sound feasible to me. A faulty switch can't create a weak spark in my head, it's either on or off. I also disagree with the statement that "electrical problems defy all logic." However, you are right, in the name of good science I will disconnect it and see if it makes a change. Thanks. Again, to me it doesn't make sense but I'll do it. (It is apparently a common mod when a frame is powder coated though.) Agreed. It does run beautifully. It's a shame there's no window into the cylinder to observe the spark hey? I guess I'll be rebuilding the whole wiring loom then! Ha. So, in short, at the moment the only un-proved systems (which are all observed to be functioning) are the switch, the wiring itself and the coil. The plug's new, the condensor's new, the points are new and the timing is perfect. I just hope in doing all this I'm not barking up the wrong tree... Thanks again and have a great Christmas.

I have read more about this phenomenon having never heard of it before. It does seem to happen sometimes. I removed the tank and carb and turned the whole bike upside down and then propped the rear mud guard up on a stool so that the engine was horizontal. I then removed the plug and spun it over fast several times by hand with the kick start. Petrol was dripping out the inlet manifold and being spurted all over the frame and the floor from the plug hole, quiet a lot. I wouldn't say 100's of ml's or anything but certainly enough to make everything wet and cause for me to clean up. Let's see how I get on after doing this. It's too late now to be starting her up but over Christmas I'll give it a go.

Wow, thanks mate. I appreciate your thorough reply. I bought the plug from Dave at Inmotion, I was there in person with my engine number getting a number of items so I am confident the plug is correct although I haven't checked. I just checked the gap and it is indeed 22thou. I did the points today and then timed it to fire at 2.5mm before TDC. All the wiring is relatively new by the last owner, the plug lead is great and I get a good spark through maybe 5mm of air to the barrel when I test it, and the barrel's painted. It was fitted by the last owner who said it's been great. He was confident that it's always run seamlessly. I don't know what model it is, the only thing I can see on it is "ISO" and "Made in Japan." I've not recorded the numbers of any jets when I cleaned them. The needle clip is on the second groove from the top, by airscrew do you mean the slide adjuster/ tick over screw? I will do. Thanks again and have a great Christmas yourself.

It has had a new one fitted by the previous owner, it looks all nice and new in good order. I was thinking about getting a replacement though but in the end I thought it's not necessary. Maybe I should. The carb is immaculate. The fuel tap works flawlessly and it's always turned off. Maybe I do..? I'd not thought of that. It would certainly change the volume of the space. I'll think about that some more, thanks. I think that's what's happening once I've kicked it a couple of times. (I also have experienced it firing up and revving up nicely, then it will just die from a high rev and just drop out, during wich time if I blip the throttle I just get aspiration noises and no more firing. Have a great Christmas guys.

Thanks mate. What is the Beta forum? Can you link me? It's the cylinder that's flooding I think, not the carb... It could be fouling the plug and prohibiting starting. It could be because of a rich mixture? (Too much fuel not enough air.) In all my testings so far I have not once witnessed "no spark," so the only electrical cause of my problem would be as you say, the spark failing under compression. I can't see anyway that this could be caused by a faulty switch, there's just no way that the switch would "know" (or be affected by) the plug being installed in the cylinder. The coil is earthed to the engine casing not an engine mountain point. The engine casing is not painted or powder coated at all. Thanks for the suggestions though. It is really appreciated.

The saga continues. Essentially the bike runs very well but is just hard to start, especially when warm. (Very hard to start... Making her un-usable.) Having bought a flywheel puller and re-adjusted the timing to be spot on, replaced the plug and condensor and consistently observe a good spark I am happy that my problem is not the ignition. The air filter is also in good order. The only remaining problem is fuel, I believe the engine to be flooding itself, the plug is very wet upon inspection after trying to start her. Could this because the mixture's too rich? Can I resolve this by lowering the needle on the throttle slide? Or am I barking up the wrong tree do you think? Cheers and Happy Christmas.

UPDATE. I removed the flywheel holding nut in the end by gently shocking it with a hammer. However, unfortunately none of my flywheel pulling tools are the right size to screw into the flywheel, they're all too small. Does anyone know any tricks to get it off without? (I've tried shocking it with a rubber mallet.)

I've been going through all of the ignition to look for faults and it's all perfect. I crocodile clipped the plug to an earth and it would spark really well all the time, every time. Everything was visually inspected and looks great, the coil does look nice and new. I then removed the timing case to have a look in there to make sure it wasn't wet or anything. Looking behind the flywheel I spotted two loose wires with uninsulated ends.. Which is not good practice obviously. Here they are: I think they must be remnants of the condensor before it was moved up onto the frame with the coil? Maybe they're safe and are not connected to anything but I want to check anyway incase they are causing me a problem. Comments welcome. I couldn't remove the flywheel for the life of me though! It's an opposite thread right? (Clockwise should loosen the nut?) I put the bike in top gear and held the rear brake on but no luck. Is there a trick to this? Thanks again.

Yeah, it has one. HaHa, never!

Thanks again for the brainstorming contributions. It's really great. It has happend when I stall the bike as well. Additionally, every time I have checked to see if there's a spark and there always is, it's always a strong blue snappy spark. If the switch was at fault then I would have experienced a scenario with no spark. This was what I was thinking (about it running well,) and is good to hear. I did think though that poorly set timing can make bikes hard to start. My Royal Enfield's both have these and it does make life easier. Any idea where I can get one? Good thinking but no, it has already been relocated up under the tank next to the coil for this reason. The previous owner has fitted a new coil and it is earthed with a wire directly to the engine casing because it's a powder coated frame and he said the earth was a problem before. Maybe I should buy a spare and just see..? All good thoughts, and thanks again but I'm still completely baffled! My Dad's going to join me in the garage over the Christmas holiday and have a fiddle, he's great with these things. Although at first he said that it's because it's a highly tuned competition bike and it could be normal but I told him it most certainly isn't! As it is it's unusable really, let alone for competition!

What about retarding the timing slightly? (Does anyone know any online tutorials to help me with this?)

Thanks bud. I've not tried that but every time this has happend I've checked for a good spark on the plug and I always get one so it does lead me to think the ignition side is fine (unless it's the timing?)

Tragically I went out for another run today and although I had great fun and the bike performs fantastically I stopped in the middle of the woods somewhere to take off some of my layers, I put the bike in neutral and pressed the kill switch. Thirty seconds later I tried to start her again. NO JOY. It's a real shame. I kicked and kicked until I was worn out, after many in's and out's of the plug, trial and error of different starting procedures she did start as if nothing had happend, randomly on a kick where I was giving it no throttle which goes against my experience yesterday. I then continued a great ride having lots of fun. Upon returning home I killed her with the switch again and couldn't re-start her at all... I returned her to the garage dismayed and not knowing what to do next. The previous owner's been in great email contact and he is just as confused as me. He did say that she's not been ridden much in the past year... He's said he's never had to start it with the throttle wide open. He also says that he always ran it on normal unleaded (on his new bike he uses Super -high octane) I'm using normal unleaded as well. (There is air, there is a spark and there is fuel, what's the problem!?? Timing?) I'm at a loss, it really puts a "spanner in the works" of an otherwise fantastic new bike. Thanks again for reading. Advice welcome.

Fantastic. This is very encouraging and just what I wanted to hear. I've never owned one before I came to this conclusion through trial and error. I think it'll be plain sailing from here on in. Cheers mate.