Fork swap

[VAL. H.]

Finaly I have space in my garage to get to work on my 89 R80 Mono Outfit.
A couple of months ago I bought a very nice pair of Leading Link forks by Wasp. On close inspection, they look practiaclly new, though there are signs of having been fitted to a bike, but I doubt it turned a wheel on the road. The forks also came with a yoke and a pair of K1100 four pot calipers.

The interesting bit is that the LL forks are actualy for a K100. Interesting because the K bike forks, even though they look identicle to the R80/100 Monos forks, actualy have 40mm over the Rs 38mm stantions. They also use conventional yokes rather than the flat steel plate on the Rs.
The LLs came with a decent set of K100 yokes, which are silver. However I happen to have a set of K75 yokes which are black, so I might use these instead.

Of corse, the bike question is. Do the K bike yokes fit the R's?
This, I have been unable to get a definate answer to. However, I'm sure I have read somewhere many years ago, that they are compatible, plus I already know that both K and Rs use the same headstock bearings, so I'm 90% certain that they will be a straight swap.

So far I have dragged the outfit out of its hiding place, where it has been under a cover for the last two years. Given it a quick wash, recharged the battery and made an attemp to start it up.

Oh dear, split fuel hose. Quickly turned off the fuel, flicked open the choke and pressed the starter anyway. Brrumm! Like it had only been in the shed a couple of days. Never ceses to amaze me this bike, seems so well sorted for such a rundown looking rig.

Some of you have read this before, but I'm going to say it again. The rig was put together by Kevin at Motorworks, so he and a mate could attend the Elefant Rally plus a few other europian winter rallies. That was well over ten years ago now, and up untill now I have kept the rig virtualy as it was when I bought it. But now it's time to move on and make it a little more user friendly.


This afternoon I started to dissasemble the front end and considering nothing has been taken of the bike in quite a long time plus all of it has beef firmly welded in place with road salt, I wasn't supprised that it took move than an hour to get the handelbars off. Christ knows how long it'll take the front wheel out. The four locking bolts are absolutely solid. Not sure I'll ever get the mudguard off in one.

Biggest bugger so far is that the speedo cable has seporated from it's head and said head is not coming off the back of the speedo.

So, First question, How do I get the threaded part off the speedo head?
Plus, Any recomendations for fuel hose E10 safe prefferably?


Val.

 

[Bubb]

Plus gas, and a long soak……the a pair of mole grips MAY release the speedo end.

If no go, try some heat afte4 soaking again in plus gas (other releasing fluids are available)

 

[mikeyboy]

Get a dremel,split the nut in two,

 

[dr nosh]

Careful with the molegrips.

Can easily distort the nut into an oval shape and make it even more difficult to get off and in the process possibly damaging the threads on the speedo. Does not matter about the nut, its scrap at this point already.

 

[Beemerboff]

Only hose you can be certain of is Auto pressure hose with the grade stamped on - I think they are up to J30 - R12 or better but
R 9 would probably do.
Usually 5.5 ID so gets a good grip on the 6mm nipples.
After fitting I like to have the float bowls off when I turn on the fuel for the first time, just in case the end of the nipple has cut off a little bit of the inner lining of the hose or whatever, and the fuel has a chance to flush it straight out instead of blocking the float valve- dont ask!

 

[VAL. H.]

Only hose you can be certain of is Auto pressure hose with the grade stamped on - I think they are up to J30 - R12 or better but
R 9 would probably do.
Usually 5.5 ID so gets a good grip on the 6mm nipples.
After fitting I like to have the float bowls off when I turn on the fuel for the first time, just in case the end of the nipple has cut off a little bit of the inner lining of the hose or whatever, and the fuel has a chance to flush it straight out instead of blocking the float valve- dont ask!

Good point I'l keep any eye out for that. Ta.

 

[VAL. H.]

Plus gas, and a long soak……the a pair of mole grips MAY release the speedo end.

If no go, try some heat afte4 soaking again in plus gas (other releasing fluids are available)

Get a dremel,split the nut in two,

Careful with the molegrips.

Can easily distort the nut into an oval shape and make it even more difficult to get off and in the process possibly damaging the threads on the speedo. Does not matter about the nut, its scrap at this point already.

Thanks for the advice guys. I've tried thw grips, but it's a bitmore difficult than that. The treaded part is going round too. I guess I'll have to strip the whole console down to get at the inside.

 

[dogshome]

+1 on the dremel. Doesn't matter if you cut in a little too far, much better than putting the hollow speedo potion out of shape.

 

[VAL. H.]

Lots of bits around the garage now. Inevetably it's not going quite as smoothly as might be. Getting the front wheel spindle out is proving difficult. All four locking bolts are seized tight and as I don't have a blow torch I guess I'll be using quite a lot of WD40. Maybe a grinder too.

Lower head bearing race is shot, how do I get it out? Not going to be as simple as getting a screwdriver on the lip and giving it a wack, though thinking about it I do have some leavers that might reach..........

 

[VAL. H.]

How The F do I get the pics upright??!!!!

 

[dean0n0]

Lower head bearing race is shot, how do I get it out?..........

I'd be looking for a length of bar, through the steering head, on to the lip. Then a hammer....

 

[VAL. H.]

I'd be looking for a length of bar, through the steering head, on to the lip. Then a hammer....

Yeh, that's the standard go too. Unfortunatley there is too much of an angle for a straight tool to reach.

 

[mikeyboy]

I MIG weld a couple of big blobs onto the outer bearing race then tap them out with a long punch

 

[Beemerboff]

Cycleworks sell a kit with a split collet which expands out between the bearing and the frame.
Not cheap but if you don't have a welder---.
I have a surplus one here but postage from Oz would probably be more than the cost of the puller!

 

[VAL. H.]

I MIG weld a couple of big blobs onto the outer bearing race then tap them out with a long punch

Ahh, yes, Welding blobs I can doo.

Cycleworks sell a kit with a split collet which expands out between the bearing and the frame.
Not cheap but if you don't have a welder---.
I have a surplus one here but postage from Oz would probably be more than the cost of the puller!

Thanks for the offer, A welder I do have. I'll give that a go.



However, I've seen a video on yuotube of someone getting the bottom race off the yoke. Looks like a big job, any tips appreciated.

 

[Hoff]

I used a Kukko counterstay and internal extractor to remove my head bearings on a 75/6.
A bit expensive but as i did not have access to a welder I took the plunge and both head outer races popped out. The extractor part do come in various sizes
I used a video on Boxer2valve to remove the bottom race off the yoke.

 

[VAL. H.]

Head bearings came out ok in the end. Thanks for the advice guys. I even managed to get the lower bearing off the yoke.

After watching someone on youtube using serious amounts of heat and cold to remove the bottom race, I was expecting this to be a right bstd to get it off. I don't have any pullers that could get even close, so I had a go with what I do have. An old 1 1/2" chisel.. I decided I would have a go at the lower race of the old forks. Working on the idea that if it didn't go well I had not buggered up the yoke to be fitted.


Next thing was the removal of the front wheel from the old forks. It only took three days, and even then I had to resort to the grinder as three of the allen heads gave out and I had to grind flats on them to get my recent putchase from Lidls toy department on there, an adjustible with a locking leaver, like molegrips have. Did the job, but one of them had to be ground right off. Considering it's been around 20 years since the wheel was last removed and a lot of salty road miles, I'm not suprised things have seized here and there. However the wheel bearings are smooth as butter.

Here's one for the knowlagable. The wheel currently has a single disc. I'm going to be adding a second disc but I noticed that the axle spacers are different sizes. Is this the same on the twin disc Monos?
It's got me thinking though. I have a set of twin calipers to go on, and I'm now wondering if the twin set calipers are centered differently to the single and that the wheel might have two equal size spacers on the twin disc bikes. Is there anything in my musings?

 

[Kenny]

I think you will find the wheel hub is also a tad narrower on twin disc bikes ( could be wrong though ). Left and right hand callipers are the same size.

 

[VAL. H.]

I think you will find the wheel hub is also a tad narrower on twin disc bikes ( could be wrong though ). Left and right hand callipers are the same size.

Not so with the Monos and K bikes Kenny. The single disc bikes have a finnishing flange on the non disc side, which is removed and the second disc fitted. I have however noticed that there are some sight differences in the width of the different discs. Basically the K100, K75, R80 mono and R100 mono all share the same front wheel. I'm almost certain too that the fork sliders (lower part) are the same castings. However the K100 & K75 have larger diametre stantions. 40mm, where the R80 has 38mm stantions. I haven't been close enough to a R100 mono with a vernier in my hand to measure it stantions but I guess it'll have 38mm's.

The postie delivered a little package today. Head set bearings, fuel pipe speedo cable and a few other bits. So I set about fitting the second disc. Yes, I know! You're going to tell me it doesn't match. Have you tided buying a sh disc for a decent price, let alone finding a matching one. Besides it's the same fitting same diameter, just looks different. Also, it's on a three wheeler, so if it does pull, it wont tip me off. Then of course if it does prove a little fisty I'll just tak it off again.

Anyway, I test fitted the K1100 four pot calipers to see mow much needs to be milled off the shouders to get them to line up. My finding is, that one side lines up perfectly. The other side is about 2.5mm out. You might say, this is due to the second disc being different. But that is the one that lines up. I'm going to fit the standard twin calipers tomorrow, to see how they line up. Might also try the oe single caliper too. See what's what.

Interesting issue with the K bike yokes. I have two sets of K bike yokes. The one's that came with the LLs, believed to be K100. The others are K75. The 100 yokes are a bit rough and the 75's are quite nice, so I thought I'd fit them instead. But there is a difference in size of about 1 1/4mm. This is enough to stop the 75s fitting on the LLs which are 41.5 in the stantions. I guess the k100 yokes are so beaton up is somone trying quite hard to get them to fit. I really don't want to use them. Tatty as my rig is, nothing is bodged. I've emailed Wasp for their thoughts on why the stntions are so oversized and if they have info on the 100 and 75 yoke sizes.

Has anyone had yokes milled out to fit a silghtly wider fork leg?

 

[Mistacat]

Your local machine shop will have no problem in boring your yokes to suit your stanchions.
These are a set of one off yokes that I machined from billets for Mikeyboy #36 https://www.ukgser.com/forums/showthread.php/572227-New-year-new-project/page3