Nigkat Posted July 12, 2023 Posted July 12, 2023 Out for a ride this evening, running fine. Overtaking a car suddenly lost power. Running poorly on 2 cylinders, 2 and 3, with a very buzzy noisy. Limped home and died just as I stopped. Tried to start it and sounds very grauncy, like cam chain is very loose. stopped straight away trying. Removed spark plugs from 1 and 4, both look OK just a bit wet. Any thoughts before I start to take things apart? Cheers Quote
johnr Posted July 12, 2023 Posted July 12, 2023 dont try to run it. get the plugs out and see if it sparks on all four when its turning over. if its 2+3 then they share a coil, so it would be buzzy going home cos it was carrying two dead cylinders. id start with electrics first cos of the fact that two cylinders on the same coil have gone off. 1 Quote
Nigkat Posted July 12, 2023 Author Posted July 12, 2023 5 minutes ago, johnr said: dont try to run it. get the plugs out and see if it sparks on all four when its turning over. if its 2+3 then they share a coil, so it would be buzzy going home cos it was carrying two dead cylinders. id start with electrics first cos of the fact that two cylinders on the same coil have gone off. Yeah cheers John, was going to be the first thing to look at but more concerned about the noise it made trying to turn it over. Quote
johnr Posted July 12, 2023 Posted July 12, 2023 its cos two cylinders are trying to carry the other two. pull out all 4 plugs, that way when you spin it over youre not fighting compression and you can see whats sparking and whats not. it might be something daft like a broken wire or bad earth. Quote
Suzukian Posted July 15, 2023 Posted July 15, 2023 Turn it over with the spark plugs out, and do it by hand. so you can feel if anything has broken inside. This will minimize any damage and possibly prevent catastrophic damage. You can check the spark with all the plugs out, but do it by hand off, once you determine the engine is turning over smoothly, then you can turn it over with the starter, you may have dropped a coil. You will have to take off one of the crankshaft covers, the right side, sitting on the bike, has the electronics, so you won't have oil coming out. Check to make sure. Quote
Nigkat Posted July 20, 2023 Author Posted July 20, 2023 Found the problem. Rear cam chain guide snapped in 2 places. All the inlet valves are sitting proud and a few marks on top of the pistons. Hopefully there won't be to much damage to guides and seats. 2 Quote
DaveV65 Posted July 20, 2023 Posted July 20, 2023 NigKat, will the inlet valves sit flush with the cam turned away from the follower? You may have bent a couple, as you say the pistons have been kissed and there's witness marks on the valves. Quote
Nigkat Posted August 14, 2023 Author Posted August 14, 2023 Stripped the head and all the inlet valves are bent. Seats look OK, just need to check the guides to see if they are worn by the bent valves. Hopefully not. What is the best way to check? Think I'll replace the cam chain. Don't really want to split the bottom cases. What do you think about replacing with a riveted up chain or bite the bullet and replace with new endless one? Quote
TonyGee Posted August 14, 2023 Posted August 14, 2023 a riveted cam chain is perfectly fine if done correctly Quote
johnr Posted August 14, 2023 Posted August 14, 2023 44 minutes ago, TonyGee said: a riveted cam chain is perfectly fine if done correctly yep, perfectly acceptable to use a rivetted link. have you got valves? Quote
Nigkat Posted August 15, 2023 Author Posted August 15, 2023 OK thanks and no not got any valves. Think mine are+ 1mm but will have to check. What is the std. Inlet valve size? Quote
johnr Posted August 15, 2023 Posted August 15, 2023 I think abuso valves are sold on Eblag in 1mm oversized. Quote
Nigkat Posted August 16, 2023 Author Posted August 16, 2023 21 hours ago, johnr said: I think abuso valves are sold on Eblag in 1mm oversized. Cheers I'll have a look. Quote
Nigkat Posted August 16, 2023 Author Posted August 16, 2023 Never heard of them before but look like just the job. They are + 1.5 mm. Very reasonably priced to, might even treat myself to some titanium retainers if I don't find anything else wrong. Quote
Nigkat Posted September 27, 2023 Author Posted September 27, 2023 My bent inlet valves were 27.5mm. I thought I had found a set, specified that I needed 27.5mm dial. I have received 27mm ones. The supplier says that they are fine. But will the seats need recutting or will they lap in OK? If they need recutting I might as well go slightly larger. ?? Quote
Nigkat Posted August 7 Author Posted August 7 Well after a full head rebuild and a few false starts, problems with ignition pickups and an iffy coil and a few other problems. Got a mot, happy days. Out for a ride Monday all going well. Came off the local dual carriageway and an almighty screeching noise. Killed the engine immediately. Pushed it home luckily not to far. Bloody hell it's heavy. Got home had a look in the oil sight glass and it was full and runny, had a sniff and it stunk of petrol. Fuck. Anyway started taking it apart today, fearing the worst and was not disappointed. It's definitely completely dead now. Pissed off to say the least. New engine time. Quote
Nigkat Posted August 11 Author Posted August 11 Top end dryer than a dry thing. Engine was ffing hot. Fuel in the oil. Well fucked that's for sure. What can cause this? Quote
Upshotknothole Posted August 11 Posted August 11 If any of the carb float valves are stuck open, they can fill the engine with fuel if the tap is open. 1 Quote
Nigkat Posted August 12 Author Posted August 12 Well Fuel tap was definitely open as I was riding at the time. Sticking float sounds about right. Quote
Upshotknothole Posted August 12 Posted August 12 It won't happen while the bike is running, happens when it's off. Fuel flows through the carb(s), down the intake, into the cylinder, past the rings, and into the engine. Quote
Safra Posted August 13 Posted August 13 Sounds like a Blocked oil galley after assembling the head on the engine or your oil pump failed from the previous tensioners pieces passing through always check a oil pump and pickup after a failure Invest in a better fuel tap the original taps are a ticking time bomb because the diaphragm or o'rings fail and lets fuel flow constantly then it washes the cylinders 1 Quote
Nigkat Posted August 17 Author Posted August 17 On 8/14/2024 at 12:40 AM, Safra said: Sounds like a Blocked oil galley after assembling the head on the engine or your oil pump failed from the previous tensioners pieces passing through always check a oil pump and pickup after a failure Invest in a better fuel tap the original taps are a ticking time bomb because the diaphragm or o'rings fail and lets fuel flow constantly then it washes the cylinders Yeah definitely sounds like that. Haven't got the oil pump out yet only top end removed. Did check pump and oil pick up before reassembly, cleaned strainer, new oil and filter. Using a pingle tap ,but is a few years old and heard of them failing. Not a lot can do now just strip and see what if anything is salvageable. Quote
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