revtothelimit - motorbike forum

Nidge wrote: Wed Sep 01, 2021 12:02 pm I’m pretty sure hot oil pressure is about 40-50 psi (I think the pressure relief valve operates at 60psi on a T140)- helpfully the oil light illuminates at 5psi … more of a “your engine is fucked” light

The oil light goes out after you start the engine. It tells you that the not intrinsically safe pump is working and you can go for a ride.

Spoke to the mechanic today...

The sludge trap is full of sludge and overflowing, so other things are full too.

The oil pump isn't screwed together fully.

Someone has poked around in there and not put it back together properly in general. It wasn't me, I didn't go that far!

He's gonna get the crank fully out and apart then see how much remedial work it needs (e.g. regrind) then put it all back together properly.

That’s a shame. A regrind and shells aren’t all that dear, but it’s all several steps backwards.

But at least they are steps.....

David wrote: Tue Sep 14, 2021 4:54 pm But at least they are steps.....

Very, very slow ones.....

It's with "the man" at the moment, but as you'd expect now that summer's over all his customers are sending in bikes for winter maintenance.

I've already paid him £650 to take it apart and find out it's broken. I already knew that

Besides, even if I got it back it's not like I'm gonna ride it. It's got far too much chrome for me to use it when there are puddles.

Mr. Dazzle wrote: Thu Sep 30, 2021 10:33 am It's with "the man" at the moment, but as you'd expect now that summer's over all his customers are sending in bikes for winter maintenance.

I've already paid him £650 to take it apart and find out it's broken. I already knew that

Besides, even if I got it back it's not like I'm gonna ride it. It's got far too much chrome for me to use it when there are puddles.

£650! How much is he going to charge to put it back together?

Potter wrote: Thu Sep 30, 2021 10:36 am I would have thought that a man of your calibre should be doing it yourself?

I've done quite a lot myself, as per this thread

The main reason I'm not doing the bottom end is space. I don't have a bench in my garage. I can do the head and similar 'cause most of the engine remains in the bike, but I don't really have anywhere to get an engine apart. I'm literally climbing over stuff in my garage as it is! Cleanliness is king when doing bottom ends so I can't really do it scrabbling around on the floor.

No, I'm not gonna do it on my dining room table. Some of you may remember from the old place the effort I went to to build that thing in the first place.

That £650 includes coming to get the bike in the van and inspecting all the bits he took out to find what's wrong BTW. E.g. measuring the crank diameters etc.

There's a really good series from Lowbrow Customs showing a complete rebuild from start to finish. It's just space and time for me really.

I am glad of the experience so far, it's been a good 'get to know you' with the bike. But fundamentally I've not learned anything about how an engine works or 'owt. I've seen some specifics about how this engine goes together, but unsurprisingly I already knew a thing or two about how they work.

Strange as it sounds, I'm not particularly interested in the specific details of how to spanner it. I'm more about the "why did they build it that way".

Potter wrote: Thu Sep 30, 2021 2:40 pm

Mr. Dazzle wrote: Thu Sep 30, 2021 12:03 pm
I am glad of the experience so far, it's been a good 'get to know you' with the bike. But fundamentally I've not learned anything about how an engine works or 'owt. I've seen some specifics about how this engine goes together, but unsurprisingly I already knew a thing or two about how they work.

So did I but there are some peculiarities and things that only come with experience.
Even something super basic like cleaning a sludge trap isn't super basic at all until you've been shown the easy way, then it's easy, but it's a chin scratcher until that point.

The problem I have is that most people that know the peculiarities of my bike are dead, they stopped making them in 1939.
There are probably a dozen blokes in the country that know more than me about the job I did on mine, and I only know what I know because one of them was kind enough to talk me through the whole thing.

That's the main issue with the older bikes, the knowledge is disappearing fast. Ok, there's the contempory owners manuals (if you can find/afford one), but that doesn't include the more recent learnings from years of ownership.

I'm somewhat lucky with the JAPton because JAP engines are pretty commonplace and their use as speedway machines means there's a lot of tuning knowledge and parts floating around (if you know where to look). Similarly, the frame is a well-known entity.

Mr. Dazzle wrote: Thu Sep 30, 2021 3:11 pm Strange as it sounds, I'm not particularly interested in the specific details of how to spanner it. I'm more about the "why did they build it that way".

Whatever was the cheapest/fastest method.

Can't go wrong with that diagnosis.

Total oppposite. Just show me the end product, IDGAS how you got there

I spoke to the man today.

It's now as far apart as it's gonna get, reassembly can begin. It doesn't need a regrind on the crank, but it will need oversized bearings. Other than that it's just of lots of cleaning and new bearings/gaskets/seals. The problem seemed to be the sludge trap was overflowing so sludge was in lots of places it shouldn't be.

Interestingly it already had oversized bearings in there, so the bottom end has been apart at least once before. No-one in the family remembers that.

Mr. Dazzle wrote: Thu Oct 07, 2021 11:55 am Interestingly it already had oversized bearings in there, so the bottom end has been apart at least once before. No-one in the family remembers that.

Obviously your bike's previous owners took the same approach to record-keeping as my Dad....

Mt FIl's approach to record keeping seemed to be "Keep every single old part you take out of the bike forever". I must've found at least 20 used sprak plugs in his garage.

Got another interim invoice today...£1000

So I now know exactly what was wrong with it. It's got lovely clean engine insides, all the oil ways have been cleaned out and checked to see that they flow properly, oil pump is rebuilt, new shell and roller bearings throughout the bottom end (that's nearly 300 notes in its own!), new gearbox bushes, new big end bolts, new little ends, polished crank shaft, new sludge trap, lots of gaskets....it goes on.

Hopefully the only invoice left is final reassembly. I toyed with the idea of getting it back to do that bit myself, but I figured I'm in this deep so I might as well give him the responsibility of making it go Brrrmmmm!

Eeek and ouch!

Money well spent.

Imagine how long it would have taken you if you'd done it yourself...,and what you might have missed//not done.

Besides, what else can you get for £1k these days?

Soon be 'brrrrmmmmmm!' day. We should have a virtual RTTL party with hats and stuff.

Is the builder any good with KX500 Supermoto's?