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Old 23-02-2019, 02:00 PM   #1
Wasta
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Monster fork problem

As you may know I bought some new forks for the Monster from Showa, they are now fitted and look lovely, but...

The axel needs a spacer on the unthreaded end, there is none required on the old forks, there was a sleeve for the threaded end which I transferred across.

Also the caliper mounting points are different centres by quiet a margin to the actual calipers.

So, question 1, does anyone on here make spacers for the forks/axel or know of a reputable company?

And question 2, should I be looking at a fabbed bracket for the calipers to mount them or source new calipers.

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Old 23-02-2019, 03:23 PM   #2
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You bought forks for a Japanese bike. They use 108mm spread between the caliper bolts. Italian and all other Euro bikes use 100mm bolt distance. That's why you also have problem with the axle.
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Old 23-02-2019, 07:09 PM   #3
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The 108 and 100mm figures for the callipers mean nothing to me. Does this refer to radial callipers?
The bolt centres for Goldline callipers are 65mm and are 45mm for the earlier ones. Probably better to get the right callipers than fanny about with brackets.
(Your '98 callipers are probably 45mm.. 65mm came in '99/2000)

Regarding the axle; did you also change the yokes? if so that would explain the different axle length required. If this is the case then putting the new fork legs in the original yokes might restore order...Possibly.

If there is now a different relation ship with the forks and wheel, there will almost certainly be a problem with the disc offset, so your callipers will not sit on the disc properly, if at all.. Something to check before buying callipers.
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Old 23-02-2019, 07:53 PM   #4
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Ah, the axle length is fine its the diameter of the axle on the right fork ( when sitting on the bike) thats different, the axle diameter is 24.9mm while the fork opening is 29.5mm. From what you said about the caliper bolt holes is correct in relation to the mounting holes.
It appears I have the forks from a 1999 onwards model.
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Old 23-02-2019, 08:29 PM   #5
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After a little google searching I think they are from an ST2 or S2R etc .So I'm thinking an axle and calipers from them should mount ok. I'll need to get some measurements to check though.
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Old 23-02-2019, 09:22 PM   #6
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Sorry about the crossed wire with the spacer re length instead of diameter. That bodes better for the disc alignment, but do check it anyway.

I don't know why there is a 29.5mm hole in one leg for a 25mm axle, perhaps it is for a sleeve nut? If you could post some pictures of your forks maybe someone could identify them to a model.

If you decide to go with a spacer, any half competent lathe operator should be able to make one if given the accurate sizes. Don't forget to split the spacer so the clamping action of the pinch bolts will still grip the axle.

It might help you to know that the 65mm centres, Goldline callipers were used on lots of post 1999 Ducatis and some Aprilia's too. Rebuild kits for those are available from Powerhouse, should you find the need.
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Old 24-02-2019, 07:06 AM   #7
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Thanks Gazza, there are a few two pot Goldline calipers with 65mm centres on ebay, I think four pots would be overkill.
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Old 24-02-2019, 08:23 AM   #8
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You want something like these;

https://www.ebay.co.uk/itm/Front-bra...QVig:rk:9:pf:0

These were used on later post '00 748, 996, ST's and Monsters like the S4/S4R and most of the IE air cooled bikes at the time except the S2R 800 which has different 2 pot sliding calipers with I think a different offset. All should have 65mm bolt spacing. I would think most had the same forks and axle except 748/996 which had different forks.So its worth checking. that.

I do know that ST4 and Monster S4 forks are interchangeable without changing anything else, they're a straight swap.
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Old 24-02-2019, 10:21 AM   #9
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As already mentioned you clearly have a pair of forks for the later model Monster or possibly the ST range but either way they have the wider caliper spacing as you have already found out.

However the fork spacer issue you have discovered is due to the later bikes having a larger diameter axle which you will need to source along with doing something to enable you to fit your front wheel as that will be for a 17mm axle.

I know changing the bearings to suit has been raised before but seem to remember it’s not quite that simple.

I lifted this from the ‘other’ forum but it’s got a pretty good pictorial of a later set up which might help you see what you’re missing/need.

http://ducatimonsterforum.org/index.php?topic=10276.0
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Old 24-02-2019, 10:37 AM   #10
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Hi Wasta.
Are these the ST2/ST4 you referenced in your earlier thread?

http://www.ukmonster.co.uk/monster/s...162#post562162

Quote:
Originally Posted by Wasta View Post
I just bought a brand new pair of Showa forks from here.

https://www.pirinimoto.it/FORCELLE-ANTERIORI

£286 delivered, they are the ST2/4 preload only. I looked at cartridge kits but they were around double the price.
Quote:
Originally Posted by Darkness View Post
That’s a good price, though the cost would go up somewhat to fit to a ‘94 as it would need different brake callipers and front mudguard.

Also is the front axle diameter bigger, needing axle, wheel bearings and spacer, and can you fit a bigger axle speedo drive with these?
It looks like the axles are bigger on those: don’t forget the speedo drive.
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Old 24-02-2019, 11:37 AM   #11
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Thanks for all the comments, this has turned into a bigger project than expected! It may be easier to source a wheel and speedo drive along with an axle from the relevant bike.
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Old 24-02-2019, 11:43 AM   #12
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You have to remember at some point (I'm not sure what year exactly because as usual there was a crossover) the speedo changed from a cable to an electronic one too.
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Old 24-02-2019, 11:48 AM   #13
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The mudguard is mounted differently too, so i think you will need that too or make some brackets to fit your old one. The later ones used plastic clips that fit around the fork bottoms in two slots whereas the older type have lugs cast into them which are higher up iirc.
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Old 24-02-2019, 12:29 PM   #14
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You mentioned 2 piston calipers in an earlier thread but be aware if they are like these S2R800 ones then I think you will need the discs to match as they are a different offset?

https://www.ebay.co.uk/itm/DUCATI-MO...rjQ:rk:30:pf:0

Perhaps someone with an S2R800 can confirm that. But from what I have read on here most with S2R800 type upgrade to the 4 piston ones as they are so much better, which is why the 2 pot ones are so cheap.
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Old 24-02-2019, 01:44 PM   #15
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Yep, disks are a different offset, which is one of the reasons I haven't done it to mine yet (that and the fact that I've just spent all my money on suspension).

The axle on my S2r is also a larger diameter at one end as well and it forms the spacer on the right hand side when sitting on the bike, thread and nut is on the left hand side - is that what you mean by spacer on the un-threaded end?
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