RH engine rebuild

[makzy]

Well there ya go, I stand corrected, like I said it’s been a while, amazing how time distorts memory.
Re powder coating, they obviously didn’t sandblast the frame before coating because the grommits and ID plate would have dissintergrated.

[lambs]

Not the engine, but I started on the frame, which needed a repair before being stripped and painted as you'll see.

The frame had been powder coated at some point, I'm not a fan.   This frame had been subject to a long-term exposure test and the coating was failing (falling off) in a number of areas.  Also there was rust here and there where the coating hadn't been applied at all + the rear master had leaked at some point stripping the coating at that location.   



Apart from the failing coating, they'd powder coated over:

- frame grommets left in place.



- the steering lock cover.



- even the ADR plate



Someone has tried to scrape off the plastic after, and there's probably enough infor for rego purposes, but I'm still going to try to remove the rest of the plastic (maybe MEK or something like that).

The RH rear side cover mounting bracket had been broken off at some point (the grommet you can see has also been powder coated):



The fracture had been powder coated so the bracket was broken prior to the frame being coated.

I found a suitable angle bracket  and bent up a replacement:



Temporarily held in place with a screw at the 'back' (at the bracket with the grommet mentioned above):



...and reshaped to match the original (having another RH comes in handy....):



Sidecover lines up OK:



I just need to sort out a suitable pin for the mounting grommet and then weld it all in place.

[lambs]

Please correct me if I’m wrong, but, are the cam cradles in a different position than an XS? It’s been 10 years since I’ve looked in there.
And yes there are several engines, both motorcycle and car, that share valve bucket type shim size.

At one point I had the original (knackered) RH head next to the XJ head on the bench and they looked the same to me in that regard, but today I did some checking.   The RH head cover fits no problem:



I pulled the RH head (not pretty) out of the shed :



.....and measured the centrelines of the cam caps with the vernier (end of gasket face as the ref), then compared that with same cap(s) on the XJ head - all came up the same distance within less than a mm or so.

Taking the original RH inlet cam and laying it on the XJ head shows that all the lobes, bearings, etc line up between the XJ head and the RH cam:

[Jonesy :-)]

We'll spotted makzy, I reckon your right, xs cam bearings or cradles as you call them are more evenly spaced,.

[makzy]

Please correct me if I’m wrong, but, are the cam cradles in a different position than an XS? It’s been 10 years since I’ve looked in there.🙄.
And yes there are several engines, both motorcycle and car, that share valve bucket type shim size.

[Christian Raith]

That's a good box of shims you have there.

[Jonesy :-)]

Precision shims are very good. cheap, fast and quality goods. I had to get a 190 shim made for my RH. Good score with the BM shims

[lambs]

Valves and valve gear installed:



I did the valve clearances on the bench:



I had a few spare shims from the damaged head, but - and this may already be 'known' - it turns out that I needed some other sizes and K-series 2 valve motors (K100 and K75) use the same 'size' valve shims.    I bought my original 'naked' K100 from a BMW mechanic and it came with some extra bits and pieces, including this:





....so shimming the valves didn't take long.

Without the shim kit, I would have gone to this guy who is not far from me:

http://www.precisionshims.com.au

I've used him before and he does excellent work.

[as an aside, with the K-series 4-valve motors the valve shim is the cam follower bucket - that's right you have to change the whole bucket to adjust the valve clearance.....]

Head in place but not bolted down yet:

[Christian Raith]

Looking forward to the finished build.
Great pictures

[lambs]

I've done a lot of engine building over the years - road/race, motorcycle and car.   One things for sure, you can't go without decent equipment:



This one was almost literally being thrown out because no-one could work out why the valve chuck had stopped working.   They're all belt drive so it was actually a simple fix....but that was not for me to say 

Exhaust valves and seats take a beating and usually the main issue unless it's a high milage engine.   The XJ head was low k's so only exhaust valves needed a light touch-up:



Neway style carbide valve seat cutters are a god-send compared to the 'old' way using seat grinding stones.   I think stones actually give a better finish, but re-facing them intermittently is a PITA.



If your valves and seats just need a light lap with grinding compound, I'd suggest getting hold of one of these gizmos:



One end attaches to your electric drill and the other end has the suction cup for the valve head.   You hold the (grey) barrel with one hand and using the drill provides the oscillating action at the valve head.   Saves wearing out the palms of your hands...

All valves done, head ready for painting:



......yes, I don't mind the odd pale ale now and then.....

[lambs]

On to the head.   As mentioned previously, I'm using a YICS head from an XJ1100.   There's plenty of info out there on what YICS is and does, so I'm not going into that here.   The important thing is that an XJ1100 is just a modified XS1100 head but turning an XJ head into an XS head is not at all difficult.

This little drilling (about 4mm in diameter) in the inlet port just 'behind' the inlet valve seat is the working end of the YICS system:



There's one of these in each inlet port.

The other end of that drilling is blanked off near the inlet port, in this case #3, but you can also see the one for #4 further over to the right.



The small drilling is connected to a much larger drilling from near the head gasket face, arrowed here:



Again there is one per cylinder, and it is this larger drilling that is blocked off to turn an XJ head into an XS head.   This image shows the drillings for cylinders 3 and 4 (1 and 2 is a mirror image):



The threaded hole 'between' the drillings is also a difference to an XS head.   It's there for an extra stud that I've removed because it's not needed for an XS11 engine.     The stud was originally there to help clamp the XJ head to the XJ cylinder block.   The XJ block has an extra passage cast in as part of the YICS system that 'links' all the inlet ports.....there's plenty of images out there.

Anyway, there's more than enough 'meat' at the large drilling to accept a 1/8" BSPT plug:



.....so after drilling and tapping + a bit of Loctite:



...job done 

[lambs]

This photo shows the indents mentioned previously on the choke shaft at carb #1:



...while at the other end (carb #4) there's no indents but a faint wear mark from the contact with the ball bearing can be seen:



Anyway, all back together and ready to bolt on:





I've used zinc plated socket head screws throughout.    Also no loctite on the gang plate screws, but spring type lock washers, mainly to make it easier to get things apart, if needed.

One final tip with regard to carb refirb that I should have mentioned earlier.   There are three carb balance adjustment screws:



To make things easier in terms of carb balance after re-assembly (esp if your carbs were more-or-less in balance before refurbishment), I suggest measuring and noting the 'gap' in the balance adjuster before disassembly for each of the 3 using a vernier caliper or similar:



After re-assembly, the balance adjusters can then be reset to their original positions.   Hopefully this will save some time, but obviously a check of balance will still need to be done with the carbs back on the engine.

[lambs]

Good, informative write up lambs. I had a similar drama of the momentarily lost choke detent ball and spring. I found a nail that fitted perfectly simulated the choke rod while carb bodies were seperated.

I only found the one on carb #4 because the ball was hanging out on a bit of residual grease.....pure luck.

The RH parts list shows the ball and spring as parts 63 and 64, also 2 of each but only in relation to carb #1.  Nothing shown in relation to #4.

[Jonesy :-)]

Good, informative write up lambs. I had a similar drama of the momentarily lost choke detent ball and spring. I found a nail that fitted perfectly simulated the choke rod while carb bodies were seperated.

[lambs]

Got a bit ahead of myself.   These are the carb bodies after painting but before re-assembly:



Paint used was VHT engine enamel in flat black.  In this case I baked the bodies after painting in my bbq at around 100C for an hour - sort of in line with what is recommended (temp gauge of sorts, but manual only control of temp  ).

I also found that a number of the the original throttle shaft seals were cracked and certainly needed replacement.