RH engine rebuild

[lambs]

[cont'd]

Replacing all the [8] throttle shaft seals required removing the throttle plate to get the shaft out.    There are 2 screws holding each plate in a machined slot in the shaft:



[note the location and orientation of stamped number on the throttle plate for later assembly]

The screws are centre-punched at the shank end by the factory to help lock them in place:



...and I found that thread locker had also been used.     Given that that if you butcher the screw head in this case you're in a world of hurt, I'd strongly recommend using a quality, close fitting screwdriver and, again, heat is your friend.

If you are successful and everything comes apart OK, it's time to check, clean and put it all back together.    I expect that getting the throttle plate back into position is something that can be fiddly.    The plate itself has marks on it from the shaft that will help:



.....but apart from that all I can say is that unless it in the right position it will 'jam' in bore...and you will know it.    When it's in the right position the throttle will 'snap' shut in a very satisfactory way.    There really is no way to describe it here, or with any amount of photographs.

I also replaced the original Phillips head screws with 12.9 zinc plated countersunk socket head screws:







These screws are stronger than the originals and the hex drive is more positive and reliable than the original type.   Loctite also used.

In terms of other parts that are needed, throttle shaft seals are available here:

https://www.motorcyclespareswarehouse.com.au/products/bdc36-325-seal?_pos=1&_sid=dabab2320&_ss=r

...but there will be other places, I'm sure.

The choke plunger boots on my carbs had gone hard, so I got replacements here:

https://www.geoffsxs.com.au/OpenCart/index.php?route=common/home

.....but I believe he has no stock of these at the moment....

I used this carb kit for replacement jets, etc:

https://www.motorcyclespareswarehouse.com.au/products/ky-0578-carb-repair-and-parts-kit?_pos=1&_sid=49217d570&_ss=r

[lambs]

I have the XJ head back from cleaning and will get to that soon, but in the meantime I did a carb rebuild.   The carb set that came with the bike was not in very good condition, not to mention some sort of paint or sealer had covered some parts, so a complete strip, clean, etc was in order.

I won't go into full details because xtian has posted a very good 'how to' article here:

http://xs1100.com.au/forum/index.php?topic=3362.0

....although there is at least one detail difference compared to RH carbs that people need to be aware of, but I'll get to that.

If there's no need or you don't plan on replacing the throttle shaft seals then I'd suggest separating the carbs isn't necessary.    In that case, I'd advise not using any aggressive solvents since that could damage the seals.    Check first, but most carb cleaners should be OK, however also be aware that some carb cleaners might also damage or even strip the RH carb body paint - not a problem if your carbs aren't painted, of course.

If you plan on doing a complete strip down than I'd give this advice:

- make sure you take notes/photos of the location of parts.
- The carb 'gang' plates are held to the carbs with screws that have thread lock applied from the factory.    There's a reason they're called 'cheese head' screws and it's not just because of their shape.   Soft buggers, and anyone that's had anything to do with 60's, 70's, 80's Japanese bikes knows why there's a big market around replacing them with socket head cap screws.
- Don't 'go crazy' on the above screws with an impact driver.   The carb bodies are thin walled castings and it would be easy to do damage.
- As described in the above linked article, vice grips (and other methods) on the screw head, and.....
- ......heat is your friend, but not too much.  Heat the head of the screw and the carb body at the screw hole, which will help break the thread locker 'bond'.    I found this method, along with vice grips on the screw head worked every time - but I have to say it took quite a lot of effort.    For heating I used a Weller portable butane soldering iron that has a heating tip attachment:



Small enough to direct the heat accurately, but also providing enough heat for the purpose.

When I finally had the carbs separated from the gang plates, a difference with the Suzuki carbs almost caught me out.   The choke plunger(s) operating shaft on RH carbs actually has 2 sets of spring loaded balls - one set on carb #1 and one set on carb #4.    The set on carb #1 matched indents on the choke shaft for the three choke positions - off, half on, full choke.     The set on carb #4 doesn't match any indents (in fact that choke shaft doesn't have any indents at that location), but appears to be there to provide extra friction on the shaft.   The spring and ball are small and easily lost if you're not aware....the ball itself is 3mm diameter:



I almost lost the spring and ball on carb #4 because I wasn't expecting them.    The arrow in this image shows were the spring+ball sit for carb #4 (similarly for carb #1).



TBC

[lambs]

I’ve always if they would fit. What about the FJ’s

According to some people on the US forums the only difference between the XJ head and the late XS heads is the YICS ports, and it has been used on XS engines without problems.      I needed a head (yeh, yeh, I've heard it before.... ) and this one was cheap enough and low k's so took a gamble.

I thought the FJ was pretty much a new design in its own right and the head is 4 valves (I think....)

[makzy]

Wondered should be after always. 

[makzy]

I’ve always if they would fit. What about the FJ’s

[lambs]

This is the head I'll be using.



It's from a low k XJ1100 so I'll be blocking off the YICS passages.    Valve stems mic up as stock - no measurable wear.   Needs a good clean so I'll have it hydroblasted, then do the valves and seats + paint.

Why XJ1100 ?.....it was cheap and the original head was knackered (badly damaged ex cam journal).

[lambs]

Thanks.  I haven't done a full rebuild of a 4cyl motorcycle engine since the 80's....a basket case Z1  (another one of those 'shoulda' bikes.....shoulda kept it  ).     I have a decent quality piston ring compressor set, but the bands are too wide and would be very difficult to get off in the available space - getting the bands onto the outer pistons would have been virtually impossible.      The 1196 pistons are 74.5mm and the slip coupling is nominally 75mm ID, I had one spare from a plumbing job so thought it was worth a try.     I think they are only a few $$ from Bunnings or similar.    Might also work with smaller XS11 pistons with a bigger section/slot cut-out.

[Jonesy :-)]

Nice work lambs, I like your backyard engineered ring compressor, I'll have to give it a go, I've previously done without, and yes steady as she goes is the name of the game

[lambs]

Set TDC and ignition rotor/pointer mark alignment.

[lambs]

Cylinder (with base o-rings installed) in place on centre 2 pistons with pistons supported by a couple of gauge blocks to ensure they're 'square' to the cylinders:



Piston ring compressor is a 20mm wide section cut from a 75mm pvc stormwater slip coupling with a 5mm (or so) slot cut, along with a suitable hose clamp (2 of, of course):



A bit of gentle tapping and a careful eye out for a piston ring popping out (or any unexpected resistance) with a bit of luck results in the centre pistons safely in place.

Outer pistons can't be supported at their base in the same way due to lack of room, but the guidance provided by the inner pistons in their bores + the associated friction makes things a bit easier.   Extra care still required to ensure outer pistons enter their respective bores squarely.     The lack of room also means that getting the piston ring compressor on and off is a bit fiddly, but patience is the order of the day.   



Again, a bit of gentle tapping with close observation means.....



Success !!

[lambs]

Pistons in place + base gasket and camchain tensioner.

[lambs]

Similar story for the alternator stator(s).  Wiring sheath was intact but had gone hard in places and would have cracked eventually, so decided to replace.   Inner stator is two wires only, so 6mm sheath used, while outer stator is 4 wire and 8mm sheath.



In this case, both stator connectors use female tabs in a plastic housing.   The tabs are held in place by a 'tang' projection and are removed out the 'back' of the plastic housing by depressing the tang.   You can see the square channel (arrowed) moulded in the housing where a suitable tool is inserted to depress the tang and remove the tab



There's a special tool for the purpose:





......but any thin, stiff steel screwdriver (eg jewellers) or similar will do the job.  Sometimes a little twisting helps.   The tab is pulled out the back of the plastic housing:



Original tab is plain brass, but I'm using zinc plated brass replacements....better corrosion resistance.   Slightly different design but does the same job.



In the case of the inner stator, I was able to push the two wires through the new sheath, but it does take some patience.  New tabs crimped on and re-inserted into the plastic housing (the tabs can only go back in one way, but in the correct polarity, of course).



The outer stator is the same story, but in that case there are 4 tabs in the plastic connector:



Generally speaking, the larger the wire bundle, the harder it gets to 'push' them through the new sheath (unless the sheath ID is 'oversized' compared to the wire bundle).    I used the 'pull through' method in the case of the outer stator loom.    One disadvantage of the 'pull through' method is that you inevitably have to use something like insulation tape to attach the draw string or wire to the end of the wire bundle.   That inevitably increases the OD of the bundle at that location and can make things more 'difficult' to pull through the sheath.   I find that a little silicone grease on the outside of the insulation tape can make all the difference.



All done.

[Plod]

Nice work - regards Kev

[lambs]

Loom repairs...I've done a lot of these so have most of the equipment and connectors.

The ignition loom was in a bad way, particularly the sheath which had gone hard and disintegrated in a number of places.

Of course, before doing anything like this, take careful note of the wire colours and their respective locations in the main connector (or connections, depending on the design of the loom).    I also measured the pick-up resistance and they were well within spec.

Note that the neutral switch connector (bottom left in first photo) 'pokes' through the sheath a distance from the pick-up end.  It was a matter of measuring the distance from that end to get it in the right place with the replacement sheath.





The old connector.   Replacing the sheath means taking this off.   To get the individual tab connectors out just requires pressing down the retaining projection (arrowed) and then pushing the old tab out the 'back' of the plastic receptacle.   A suitable small screwdriver (jewellers or similar) or something similar will do the job.



After being pushed out, the old tab (in this case the neutral switch wire) is shown at top.   They all look the same apart from wire colour.  Next to it is shown the tab I'll be using as the replacement.    The new tab is slightly larger being FASTON 1/4" (6.3mm) standard, while the original was 6mm 'Japanese' standard.    The difference doesn't present any major issues in this case.....and the FASTON type are easier to source.   The original and replacement tabs are zinc plated brass for corrosion protection.   Plain brass tabs are also available, but best to use the zinc plated type.



Sheath material is readily available (ebay, whatever) and comes in different bore sizes.   In this case comparing with the old sheath showed that 8mm bore material was close enough.   



It's not possible to push the wires through the new sheath with the old tab connectors in place, so they are cut off leaving as much of the original wires intact as possible.     Once that's done, it's 'just' a matter of pushing the wire bundle through the new sheath.....easier said than done depending on the number of wires and the overall length they are to be 'pushed through'.    No photographs or video can cover this.  It can take a lot of patience and the only tip I can give as that it is best to keep the new sheath laid as straight as possible....any curves increase the resistance to the wires passing through.

To get the neutral switch wire into place I used a piece of stiff wire to pull it through.    After 'nicking' a small piece out of the new sheath at the appropriate location using a wad punch, I forced a length of stiff steel wire through the sheath from that location to the connector end, attached the neutral wire using electrical tape (first photo) and than used the steel wire to pull the neutral wire through the new sheath.  The second photo shows the neutral switch connector in place.





Once all the wires are in place in the new sheath, it's a matter of wire stripping and crimping on the new tab connectors.   The tabs are then inserted into the plastic receptacle, making sure the wire colours match their original locations and they 'lock' into place.



In this case the new tabs are slightly longer than the originals but nothing a dremel won't fix, if needed.

All done:



All mounted up:



Phew......

[lambs]

I'm detecting a theme.....

I'm a long way from engine start, and it can be done with the engine in the frame so plenty of time to sort that gasket yet.