Good video, I like the way you demonstrated your diagnostic skills. I have owned and rebuilt the older air cooled RD's, and I own a YPVS which I have rebuilt. (We never got the LC in the US.) Two things jumped out at me from your video. 1. Why was the right cylinder head dry? 2. What caused the big end bearing to fail? This could be an oil problem, an air leak problem, or a coolant leak problem. Be sure to look for clues as you dismantle the engine. Trust your observations, I think you will get it sorted out.😊 Be sure to leak down test the reassembled engine for air leaks, particularly, the carb boots and intakes. A little extra work, but well worth it. Looking forward to seeing the next video.
@@Scott-ph2yk thanks Scott, in the next video I will be looking into why this has happened as we don’t want this to damage the new engine, thanks again for the advice, cheers 👍
Great video. Loved the raw, unedited approach you took to analyse the problem. Brings back memories when I bought a new RD350LC back in 1981. I look forward to the engine re-build in your next upload. Thanks again and take care.
Pissed 'n' Broke. A fried of mine was just putting a new crank in a KH250 when I said to him "you know you've got bubbles in the autolube pipe, looks to me as you have an oil pump failure.
I’ve had a couple of these bikes, and became very familiar With them. I used to be able to strip my 250LC down to the crankshaft in half an hour. Having the crank vases split horizontally was a good idea. It’s a shame the bike didn’t come with the standard pipes, although our experience, the Kenny Roberts replicas came with e from new (ugh - horrible things!). I had a tuner race-tune my 250. It flew but got through petrol faster than 20mpg😬. You
@@MeYou-yz2yz only had air cooled 200 an they never had 1, not something I've heard of on air cools either. Just presumed was pipe straight down to pump.
I would have thought that the piston would seize before the big end would let go if the oil pump was the issue. I love 2 smokers but they generally are a 'ticking- time bomb' The only cure for this is to give everything a life span. I had a highly tuned 350 LC back in the day, the power band started at the standard red line, it then revved to 11.5k RPM. The crank was good for 5k miles, the pistons were good for 7k miles. The crank was welded up to stop it twisting and it ran TZ big end bearings which are less prone to skidding. It took a lot of work to keep that engine running!
Good video, I like the way you demonstrated your diagnostic skills. I have owned and rebuilt the older air cooled RD's, and I own a YPVS which I have rebuilt. (We never got the LC in the US.)
Two things jumped out at me from your video. 1. Why was the right cylinder head dry? 2. What caused the big end bearing to fail? This could be an oil problem, an air leak problem, or a coolant leak problem. Be sure to look for clues as you dismantle the engine. Trust your observations, I think you will get it sorted out.😊
Be sure to leak down test the reassembled engine for air leaks, particularly, the carb boots and intakes. A little extra work, but well worth it.
Looking forward to seeing the next video.
@@Scott-ph2yk thanks Scott, in the next video I will be looking into why this has happened as we don’t want this to damage the new engine, thanks again for the advice, cheers 👍
Great video. Loved the raw, unedited approach you took to analyse the problem. Brings back memories when I bought a new RD350LC back in 1981. I look forward to the engine re-build in your next upload. Thanks again and take care.
Pissed 'n' Broke. A fried of mine was just putting a new crank in a KH250 when I said to him "you know you've got bubbles in the autolube pipe, looks to me as you have an oil pump failure.
I’ve had a couple of these bikes, and became very familiar
With them. I used to be able to strip my 250LC down to the crankshaft in half an hour. Having the crank vases split horizontally was a good idea. It’s a shame the bike didn’t come with the standard pipes, although our experience, the Kenny Roberts replicas came with e from new (ugh - horrible things!). I had a tuner race-tune my 250. It flew but got through petrol faster than 20mpg😬. You
Nice roberts rep! Ring a ding ding!
Cranks used to go on the air cooled rd 250's before the lc. Went on my bike 250 E. After I sold it. 1980
Sweet bike love a 350lc
Bore it first oversize. crank rebuild and new rods . It will be as good if not better then new !!!. Pretty bike too !!!
Bores not seen conrod little end not seen.
Hoping for a bit more detailed probable cause analysis in next vid.
Need to get oil pump checked cos oil starvation will have caused big-end to blow.
A blocked strainer on the oil tank caused the destruction of big-end on my air-cooled rd.
@@MeYou-yz2yz only had air cooled 200 an they never had 1, not something I've heard of on air cools either. Just presumed was pipe straight down to pump.
I would have thought that the piston would seize before the big end would let go if the oil pump was the issue. I love 2 smokers but they generally are a 'ticking- time bomb' The only cure for this is to give everything a life span. I had a highly tuned 350 LC back in the day, the power band started at the standard red line, it then revved to 11.5k RPM. The crank was good for 5k miles, the pistons were good for 7k miles. The crank was welded up to stop it twisting and it ran TZ big end bearings which are less prone to skidding. It took a lot of work to keep that engine running!
That's NOT aluminium ... It's METAL !!! THINK ABOUT THAT COMMENT !
Well spotted😂
Y'all gotta clean the excess burn 🔥 carbon buildup off them heads like ye olde X6?
It’s rooted I’ll get rid of it for him
great job lad the joj ov 2 bangers could have been worse next video please
love it yamaha…..
When your getting paid by the minute lol
That's Gold 😂 yeah he definitely padded out this video 😅😂😂
@@alanbirch9663 well the video went for 22 mins so that’s a pretty good deal for that much work?
feature not a fault
man….update your rx125…..