Title: my Ktech 996 fork upgrade on S4 Post by: jerryz on November 10, 2011, 08:26:48 AM my Ktech 996 fork upgrade on S4
well finally got the Ktech 996 forks to thailand and fitted to the S4 , a lot faffing around with lower yoke shims 0.5mm and the tope yoke Capo supplied was for fat bars so i had to make shims to fit my 7/8 bars as fat bars are stupidly expensive in Thailand and would foul the stanchions anyway as the 996 SHOWASforks are 10mm longer than S4 Showas . well been avidly testing the bike this week over 200 miles so far and things are a massive improvement on the old setup. The New forks came from a 996 off Ebay for $180 and were sent away for Ktech revalves, overhaul , 5w oil and 8.5 spring set for my weight , all in i spent about $850 ORIGONAL S4 SHOWAS ARE NOT WORTH SPENDING MONEY ON AS THEY HAVE A DESIGN FAULT ! first i have noticed a big improvement in stability on corners and straights ,much more precise control , i have changed a few settings on rebound and compression they are now set at 6 clocks compression and 8 clicks rebound , sag is 20mm but preload is minimal on 7 lines visible i still think the forks are a little hard and could be plusher on the bumpy bits but the airgap was set by ktech at 120mm as a average starting point and i will remove some oil as i want it a bit softer maybe 130mm or even 140mm airgap using 5w oil. i have upped the rear ohlins compression 2 clicks as well bike feels very balanced now . was it all worth it , am i happy .....definitely ......but the quest for perfection goes on __________________ MONSTERMAN Title: Re: my Ktech 996 fork upgrade on S4 Post by: Speeddog on November 10, 2011, 10:48:50 AM Glad it worked out well! [beer]
Motivates me to fit the SBK guts to my forks. Title: Re: my Ktech 996 fork upgrade on S4 Post by: brad black on November 11, 2011, 11:51:40 PM i watched a set of 2006 1000ss forks come apart on monday and they were long rebound rod style like the sbk forks. never seen that in a 50/54 fork before.
Title: Re: my Ktech 996 fork upgrade on S4 Post by: greenmonster on November 12, 2011, 04:34:15 AM Did they look like fig 6 here http://www.ducatimonsterforum.org/index.php?topic=49759.15 (http://www.ducatimonsterforum.org/index.php?topic=49759.15) ?
Title: Re: my Ktech 996 fork upgrade on S4 Post by: jerryz on November 12, 2011, 05:18:24 AM The oddest thing is that the cheapo standard Showas with the crappy short rebound work well on my M750 and 750ss they also have no adjustments and i dont miss it ...maybe its the lighter weight or less power ??? the S4 now feels as sharp as they do with the new fork setup,,, strange aint it
Title: Re: my Ktech 996 fork upgrade on S4 Post by: MonsterHPD on November 12, 2011, 11:48:37 AM hello,
a couple of members of the Swedish Ducati Club are building trackday bikes with Pierobon frames and big 2V engines, and one of them asked my advice on what to do with the forks from the 1000DS /SSie donor bikes. Not knowing better, I adviced him as per my fork mod piece published earlier, but after a while he sent me the pic below: (http://i855.photobucket.com/albums/ab117/Monsterhpd/1000SSie-03-1.jpg) This suprised me a bit; I have not actually ridden a 1000DS/SSie bike, but I have made the open / closed rebound "bounce test" on one and found nothing to make suspect they are any different from other 50/54 Showa forks. Well, they are, the have a "proper" rebound damping circuit layout, but apparently with very ineffective valving. The Pierobon guy confirms this after a season of track riding, by the way. The good news is that these forks can be upgraded with a Ktech piston/shim kit without manufacturingany new parts. The forks will work as well as any forks with 20 mm cartridges with this mod, and I daresay, better than any standard Duc SBK forks. Sticking my neck out a bit there, since there are a lot of then that I´ve not been into, but at least they will work much better than stock .... Here is saturday night, so I´ll have a [drink] feel free to join ;D Title: Re: my Ktech 996 fork upgrade on S4 Post by: brad black on November 12, 2011, 03:59:21 PM hello, a couple of members of the Swedish Ducati Club are building trackday bikes with Pierobon frames and big 2V engines, and one of them asked my advice on what to do with the forks from the 1000DS /SSie donor bikes. Not knowing better, I adviced him as per my fork mod piece published earlier, but after a while he sent me the pic below: (http://i855.photobucket.com/albums/ab117/Monsterhpd/1000SSie-03-1.jpg) This suprised me a bit; I have not actually ridden a 1000DS/SSie bike, but I have made the open / closed rebound "bounce test" on one and found nothing to make suspect they are any different from other 50/54 Showa forks. Well, they are, the have a "proper" rebound damping circuit layout, but apparently with very ineffective valving. The Pierobon guy confirms this after a season of track riding, by the way. The good news is that these forks can be upgraded with a Ktech piston/shim kit without manufacturingany new parts. The forks will work as well as any forks with 20 mm cartridges with this mod, and I daresay, better than any standard Duc SBK forks. Sticking my neck out a bit there, since there are a lot of then that I´ve not been into, but at least they will work much better than stock .... Here is saturday night, so I´ll have a [drink] feel free to join ;D that's them. surprise dme too. i did a blog post on it - http://bradthebikeboy.blogspot.com/2011/11/1000ss-fork-job.html (http://bradthebikeboy.blogspot.com/2011/11/1000ss-fork-job.html) Title: Re: my Ktech 996 fork upgrade on S4 Post by: brad black on November 12, 2011, 04:01:14 PM The oddest thing is that the cheapo standard Showas with the crappy short rebound work well on my M750 and 750ss they also have no adjustments and i dont miss it ...maybe its the lighter weight or less power ??? the S4 now feels as sharp as they do with the new fork setup,,, strange aint it the problem with the adjustable ones is the location of the bypass valving. i see no reason why that would effect a non adj as they have different cartridges. having no adjustment isn't an issue, except in people's minds. Title: Re: my Ktech 996 fork upgrade on S4 Post by: ducpainter on November 12, 2011, 04:09:24 PM <snip> having no adjustment isn't an issue, except in people's minds. Title: Re: my Ktech 996 fork upgrade on S4 Post by: Curmudgeon on November 12, 2011, 07:41:57 PM having no adjustment isn't an issue, except in people's minds. ain't that the truth [thumbsup] :) :) :) Title: Re: my Ktech 996 fork upgrade on S4 Post by: jerryz on November 13, 2011, 06:22:59 AM well i have no intention of ever messing with the forks on the M750 or 750ss other than routine servicing and 5w oil as they work just fine for me ..
the s4 has been an entirely different journey over the last 4 years and now its all about done ....i cant think of any mechanical improvements for handling or power etc that will make it any better that i have not alredy done...so next thing will be cosmetics as she could do with a tart up she runs brilliantly and now handle surefootedly ,shes a keeper as in Thailand i could never hope to recover more than 25% of what the bike has cost me . the airgap is to hard at 120mm thats sure i put tie wraps on the forks and after 200 miles of hard riding they are still 30mm up the legs the forks can be set softer in this environment ,the roads are bumpy ...i am going back to work next week and wont have time to do this task till january then I will up date again will go to 140mm airgap for plushness Title: Re: my Ktech 996 fork upgrade on S4 Post by: jerryz on November 15, 2011, 06:28:35 AM PROBLEM....Oh dear the forks are too hard i have now set zero preload and zero comprssion with 5 clicks rebound and removed some oil so air gap is a massive 140mmm and they are just about compliant on the local racetrack and perfect roads ...several mates have now ridden the bike around Bira track and we have come to conclusion that either springs are too hard or HM racing fitted the wrong Ktech valves ????? also static sag is ZERO !!!!!! the handling is great but comfort is zero ,,,,something not right ...I will have to bring the forks back to UK next year in meantime the bike is ridable and very accurate , i am taking corners much quicker and at greater lean angles also doing stoppies which old forks would never do but my wrist are bruised after a 150 mile ride today , my brief to HM racing was road focused forks for comfort and accuracy .
HO HUM !!!!!!!!!!! Title: Re: my Ktech 996 fork upgrade on S4 Post by: Privateer on November 16, 2011, 04:49:16 PM It all sounds magical. My biggest complaint with my bike is the suspension. I was riding behind my buddy the other night and his headlight (not ducati) was solid as a rock on the highway, mine was bouncing all over the place. And yes, I've had them professionally adjusted.
is there a link available to this product? Title: Re: my Ktech 996 fork upgrade on S4 Post by: jerryz on November 18, 2011, 06:39:33 AM seems the spring is a 9.5 and that its the lightest made for 996 forks by k tech which is ridiculous as I specified 8.5 by my own calculations ,
HM racing and k tech now tell me they cannot supply a 8.5 or less spring for 996 forks and that 9.5 or 10 is what is used in race bikes......they said i shoild start trimming the preload spacers ?????? i am not a happy bunny about this at all. maybe ohlins do a lighter spring ???? __________________ MONSTERMAN Title: Re: my Ktech 996 fork upgrade on S4 Post by: Speeddog on November 18, 2011, 08:55:57 AM This says they go down to .85:
http://www.kneedraggers.com/product/668647/K-Tech-Suspension-Front-Fork-Spring-Kit-Ducati-996-With-Showa-Forks (http://www.kneedraggers.com/product/668647/K-Tech-Suspension-Front-Fork-Spring-Kit-Ducati-996-With-Showa-Forks) Perhaps the 996 springs are different from what's in your hybrid forks.... Title: Re: my Ktech 996 fork upgrade on S4 Post by: MonsterHPD on November 18, 2011, 10:12:03 AM I looked for a long time for springs with spring rates lower than 8.5 N/mm. I´ve tried a set of 8.5´s, but they were definitely too hard for me (approx. 73 kg with gear).
Since I could not find any springs that would go in without modifying spacers and such, I decided to use the springs for the Öhlins R&T forks. They are almost identical in diameters to the stockers, but beeing made from higher-grade wire (presumably ...), they are shorter with steeper pitch. One reason to use them are that they ae available in rates from 7 or 7.5 N/mm up to 11.0 N/mm, in 0.5 N steps. I used the same rate in my Showas as I do in my Öhlins R&T fork, i.e. 8.0 N/mm which works very well (part number 4745-80 acc. to the invoice). I had to manufacture new pre-load tubes, a coupler piece between the tube and spring, and slightly modify the plastic spacer on top of the pre-load tube. Installed pre-load with fully backed-off adjuster is between 5 and 10 mm, should not be more than 10 mm. I did some snapshots so I´ll do a how-to one of these days; this picture will give you an idea: (http://i855.photobucket.com/albums/ab117/Monsterhpd/Springcomparo.jpg) BTW, I think some parts are on their way from K-Tech for the cartridge rebuild / modification, so that how-to will also appear one of these days ;) Title: Re: my Ktech 996 fork upgrade on S4 Post by: jerryz on November 19, 2011, 06:31:12 AM Monster HPD ...could I cut some metal off the spacer tube say 10-20mm might reduce the preload by 1nm ???that would be the simplest method.I want about 8nm -8.5nm springing for road use .
Title: Re: my Ktech 996 fork upgrade on S4 Post by: Speeddog on November 19, 2011, 10:13:01 AM Monster HPD ...could I cut some metal off the spacer tube say 10-20mm might reduce the preload by 1nm ???that would be the simplest method.I want about 8nm -8.5nm springing for road use . That'll just change your sag, it won't effect the spring rate. Title: Re: my Ktech 996 fork upgrade on S4 Post by: MonsterHPD on November 19, 2011, 02:51:53 PM Right, cutting the preload will just affect the sag, suspension action will be just as stiff.
I´ve been digging out my old invoices for stuff I´ve bought for the bike (scary reading ... :o ), and I think I´ve found the invoice for the 8.5 N/mm Öhlins springs I tried first. The part number stated on the invoice is 8700-85, and these springs should be a straight drop-in in some Ducati SBK fork or other; I couldn´t say which one, though. I think it would be pretty easy to install in any SBK fork; for the Monster fork I made an additional preload tube out of a stock SBK preload tube (if memory serves, the SBK forks have a preload tube under the spring, in the bottom of the fork leg). If I wanted an 8.5 N/mm spring in an SBK fork, I´d check this option for sure. Title: Re: my Ktech 996 fork upgrade on S4 Post by: jerryz on November 22, 2011, 06:10:10 AM I contacted ohlins and they said they could no longer supply 8 or 8.5 springs for 996 forks but I also contacted racetech who say they can supply an 8 or 8.5 spring for 996 fork ?????????
Title: Re: my Ktech 996 fork upgrade on S4 Post by: MonsterHPD on November 22, 2011, 09:26:16 AM Ooops, too bad, sorry for providing that piece of useless info.
I suppose if Racetech says they have 8.0 or 8.5 springs, that would be the easiest option, then. Title: Re: my Ktech 996 fork upgrade on S4 Post by: Speeddog on November 22, 2011, 10:23:45 AM I contacted ohlins and they said they could no longer supply 8 or 8.5 springs for 996 forks but I also contacted racetech who say they can supply an 8 or 8.5 spring for 996 fork ????????? These folks said they can provide the Ohlins springs (4745-80 for example, I just called them): http://www.kyleusa.com/ (http://www.kyleusa.com/) They're here in California. Title: Re: my Ktech 996 fork upgrade on S4 Post by: jerryz on November 24, 2011, 07:57:44 AM its nice to have options , i will wait until i get home from offshore job to open up the forks and double check exactly what weight of spring is in them then i will decide what action to take , i am now confused as I was told they had put in 8.5 Ohlins springs but that seem impossible now and that 9.0 or 9.5 ohlins spring was put in .
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