Grab this you SH clucthes!
01-23-2019, 01:21 AM
#1
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Grab this you SH clucthes!
As most SH owners know our clutches can be a bit grabby when trying to launch at high RPM or even causing stalls when trying to leave from a stop by slipping the clutch. I've read about the reasons (poor design, V twin torque Etc.) and the remedies (weaker springs, Varadero cable clutch conversion, Etc.) over the years. Last year I installed a 800 VFR master cylinder as I wanted the built in reservoir. I discovered that it has a 14mm bore vs the stocker at 15.87mm. (5/8 in) This changed the lever to slave ratio a bit and made the engagement point a little broader. I was willing to put up with slightly longer lever travel and it helped but , not quite enough. And then, Thanks to Erik and this forum, I found the Oberon slave cylinder. Installed it last night and I can now slip the clutch without the gabbiness! I think it is due to the 2mm increase in bore size over stock. Yes it increased the lever travel slightly as it increased the ratio even more coupled with the VFR master. This even widened the engagement point more. But, it worked! It behaves like I was hoping. Smooth action, broad engagement. If I did the math right the stock ratio was 2.24:1 and the VFR/Oberon is 2.69:1 That slight change was all it needed. The only bad thing is that took me 6 years to figure it out!
01-26-2019, 10:09 AM
#2
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Squid
Join Date: Dec 2018
Posts: 14
I own my VTR some months ago, ( I have done 5000 Km so far) and one of the things that I don´t like is the clutch performance. Most of the handle movement is useless and the clutch actuates just in the last part.
I changed the clutch disks the first month, thinking that maybe they were worn, but it didn´t solve anything about this " issue" then I noticed that the problem was, ( in my opinion ) an excessive travel in the clutch.
Thinking about your smart solution, I have been looking for handle clutch with 13mm piston, diameter, that combined with the oem slave piston should act like your actual VFR-Oberon. There are many around, ( some expensive brembo units also) and I´m trying to find a motorcycle that uses a 13mm piston in order to buy a second hand unit..
Edited:
Seems that the brembo PS13 rec from ducati 600 and 750 can be an option.
I changed the clutch disks the first month, thinking that maybe they were worn, but it didn´t solve anything about this " issue" then I noticed that the problem was, ( in my opinion ) an excessive travel in the clutch.
Thinking about your smart solution, I have been looking for handle clutch with 13mm piston, diameter, that combined with the oem slave piston should act like your actual VFR-Oberon. There are many around, ( some expensive brembo units also) and I´m trying to find a motorcycle that uses a 13mm piston in order to buy a second hand unit..
Edited:
Seems that the brembo PS13 rec from ducati 600 and 750 can be an option.
Last edited by Felix Barrao; 01-26-2019 at 10:50 AM. Reason: Info added
01-27-2019, 06:18 AM
#6
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Location: Montreal
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In the event that the question is for me, the radial MC is a 15 x 18, meaning the piston diameter is 15 mm and fulcrum measurement is 18 mm, the latter measurement being just as important as the first when considering the mechanical advantage it affords. In the end, it works...
01-27-2019, 07:14 AM
#7
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Squid
Join Date: Dec 2018
Posts: 14
In the event that the question is for me, the radial MC is a 15 x 18, meaning the piston diameter is 15 mm and fulcrum measurement is 18 mm, the latter measurement being just as important as the first when considering the mechanical advantage it affords. In the end, it works...
01-27-2019, 10:35 AM
#8
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Squid
Join Date: Dec 2018
Posts: 14
As most SH owners know our clutches can be a bit grabby when trying to launch at high RPM or even causing stalls when trying to leave from a stop by slipping the clutch. I've read about the reasons (poor design, V twin torque Etc.) and the remedies (weaker springs, Varadero cable clutch conversion, Etc.) over the years. Last year I installed a 800 VFR master cylinder as I wanted the built in reservoir. I discovered that it has a 14mm bore vs the stocker at 15.87mm. (5/8 in) This changed the lever to slave ratio a bit and made the engagement point a little broader. I was willing to put up with slightly longer lever travel and it helped but , not quite enough. And then, Thanks to Erik and this forum, I found the Oberon slave cylinder. Installed it last night and I can now slip the clutch without the gabbiness! I think it is due to the 2mm increase in bore size over stock. Yes it increased the lever travel slightly as it increased the ratio even more coupled with the VFR master. This even widened the engagement point more. But, it worked! It behaves like I was hoping. Smooth action, broad engagement. If I did the math right the stock ratio was 2.24:1 and the VFR/Oberon is 2.69:1 That slight change was all it needed. The only bad thing is that took me 6 years to figure it out!
01-27-2019, 11:56 AM
#9
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That is how mine is set up now, early year non integrated res OEM master cylinder with a fresh all service part rebuild, new res cup, SS braided line and the Oberon slave...Very happy with it
01-27-2019, 12:09 PM
#10
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Squid
Join Date: Dec 2018
Posts: 14
Seems that the Oberon is the best option then, before trying smaller master cylinders..
01-28-2019, 11:22 PM
#11
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Felix, You are correct, my bad! Apparently the PO had put an unknown (possibly Suzuki SV) 5/8" (15.87mm) master on in an effort to widen the engagement point. As some of us have discovered, that was going the wrong way. You can imagine how grabby my clutch was with that setup! My old *** really thought I was on to something when I changed to the 14mm integrated VFR master. Regardless of my faux pax, 14mm with the Oberon works perfect.
Sorry about any confusion.
Sorry about any confusion.
02-02-2019, 09:23 AM
#15
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Yes but it also matters what calipers you are running. Then it is what "feel" you are going for.
I haven't run a VFR master but with the SP stuff I found The SP2 master a much better option but it is also what works for me.
Granted I do have a complete SP2 front end on my bike but I have also set up bikes with stock calipers & SP2 master and have had good results.
Though now days, if I was starting over, I would source a newer style radial master cylinder.
02-03-2019, 01:11 PM
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02-12-2019, 04:57 PM
#19
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02-13-2019, 04:06 AM
#21
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Yes not sure, I never thought there was anything wrong with the VTR clutch other then the chatter if you released it way to quickly. I needed to rebuild a slave cylinder so thought Id try the Oberon... It not only worked, but it does in my opinion give a better lever feel then the OEM slave,
02-13-2019, 08:51 AM
#22
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Jaime and Eric, Yes, "Chatter" is more descriptive. It must be random as out of two fellow SH owners and myself, two chatter and one is fine. In fact one (a '99) chatters if you slip the clutch at speed. So, I guess I should have stated "Many" instead of "Most" The only time it happens is when launching from a standing start. As when running on a drag strip, Etc.
Both of the "chatterers" were cured with Oberon Slaves. I think due to the design and the 2mm bigger cylinder.
Both of the "chatterers" were cured with Oberon Slaves. I think due to the design and the 2mm bigger cylinder.
02-18-2019, 05:48 AM
#26
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Pick a dealer or order direct
http://www.oberon-performance.co.uk/...n-Dealers.html
http://www.oberon-performance.co.uk/...n-Dealers.html
02-19-2019, 04:38 AM
#28
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Same here, same time frame....
And post service with leadership at the company was excellent as well.
The buddy I learned about Oberon from, bought his off a Oberon Ebay ad... and had it in the same time frame, but it came from a Canadian dealer
And post service with leadership at the company was excellent as well.
The buddy I learned about Oberon from, bought his off a Oberon Ebay ad... and had it in the same time frame, but it came from a Canadian dealer
02-19-2019, 09:19 PM
#29
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For me the VTR clutch is by a mile the worst clutch set up I have ever experienced. If you rev the motor even a bit too high and try to release the clutch you get violent chatter and grabbing that is in my opinion dangerous. On my CBR600 I could redline the bike and slip the clutch all the way to turn 1 if I had to but try that on the hawk and you'd get flipped violently. I have 2 hawks and they are both like that and everyone else on here seems to have similar experience.
02-19-2019, 10:27 PM
#30
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First think I did after buying my VTR was to change the clutch discs, thinking there were something wrong with them... Nothing changed after. The Oberon has been a big improvement. I´m happy now, but probably next think will be a 13mm brembo clutch master instead of the 14 oem one.
I bought the oberon directly from the manufacturer
I bought the oberon directly from the manufacturer
