Author Topic: Harsh Cer Forks.  (Read 28454 times)

Offline motoddrob

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Re: Harsh Cer Forks.
« Reply #255 on: April 01, 2019, 05:35 »
After servicing the Marzos on the Motodd and drilling an extra hole in the Racetech valves, set the original silver spring at 3 turns, 150mm air gap and took out a 15mm preload spacer and using 15wt oil the front end has been transformed. Think I might even play with the WP rear shock now, probably room for improvement after using the same setting for 34 years!!!
I don't really fuck with settings, I just ride the fuckers 8)
Motodd 1200, SFC750

Offline cbertozz

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Re: Harsh Cer Forks.
« Reply #256 on: April 01, 2019, 05:47 »
Mine is the same except its got 5 washers to get to a good sag distance of 35ish mm. That's with a 9.5 spring. Me at 125kg as well. We can not compare valve adjustments obviously, mines a Race Tech and yours in that NZ one.

When I get things right the bike is like it's on rails. I was a little short on sag for road at 25mm at front, back same 25mm and isn't using more than 70% of spring travel.
1978 Laverda Jota #6041
First owned in 1991, reacquired 2016.

Offline motoddrob

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Re: Harsh Cer Forks.
« Reply #257 on: April 01, 2019, 06:48 »
When I get things right the bike is like it's on rails. I was a little short on sag for road at 25mm at front, back same 25mm and isn't using more than 70% of spring travel.

The beauty with the Motodd frame, it doesn't matter what the settings are they always ride like on rails ;D
If your ever in my neck of the woods you can try it out on my test track
Motodd 1200, SFC750

Offline cbertozz

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Re: Harsh Cer Forks.
« Reply #258 on: April 01, 2019, 07:27 »
Hard to turn down!
1978 Laverda Jota #6041
First owned in 1991, reacquired 2016.

Offline cbertozz

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Re: Harsh Cer Forks.
« Reply #259 on: May 15, 2019, 17:10 »
I've bitten the bullet and gone a pair of top-line Nitrons from DAM Laverda. Like Ohlins, they are far from cheap, but are the bees knees. I figured i won't be doing any more custom builds on this bike, so I finally want to finish what i started two or three decades ago right.

Very much looking fwd to reporting back on them ...

Have you had a chance to try them out yet? My first impressions were very good, although I feel that they may be a tiny bit under-sprung for me but time will tell.
1978 Laverda Jota #6041
First owned in 1991, reacquired 2016.

Offline Piranha Brother 2

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Re: Harsh Cer Forks.
« Reply #260 on: May 16, 2019, 09:34 »
Nor tried yet - bike is still some months off. Frame work in progress at the mo. Change of springs is no drama. With slow and fast rebound plus comp damping adjustability, there's a bit to get right.
What ... leave it standard??!!

Offline cbertozz

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Re: Harsh Cer Forks.
« Reply #261 on: May 21, 2019, 08:04 »
A couple of days at Collie should be a good shakedown.
1978 Laverda Jota #6041
First owned in 1991, reacquired 2016.

Offline AndyW

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Re: Harsh Cer Forks.
« Reply #262 on: August 22, 2019, 09:58 »
Hey Vince, got those new shock springs yet? any good??
'71 TR6 Tiger, '73 X-75, '73 3C, '74 3C, '75 SF2, '75 850T3 Cal, '75 T160V, '78 Mirage, 78 SSD Darmah '80 SD Darmah, '82 TR7/T, '83 Tenere, '85 R80g/s, 2017 MV F3 (Ago edition)

Online Vince

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Re: Harsh Cer Forks.
« Reply #263 on: August 22, 2019, 10:25 »
Yes i have it feels good when you bounce it no test ride yet it needs another 1/2 turn off the emulator spring preload

Offline AndyW

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Re: Harsh Cer Forks.
« Reply #264 on: August 22, 2019, 19:01 »
Emulators in the rear?? What sort of shocks have you got??
'71 TR6 Tiger, '73 X-75, '73 3C, '74 3C, '75 SF2, '75 850T3 Cal, '75 T160V, '78 Mirage, 78 SSD Darmah '80 SD Darmah, '82 TR7/T, '83 Tenere, '85 R80g/s, 2017 MV F3 (Ago edition)

Online Vince

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Re: Harsh Cer Forks.
« Reply #265 on: August 23, 2019, 03:25 »
No the emulators in the forks i know i shouldnt change 2 things st once but its taking 2 long between tests

Offline Laverda SF

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Re: Harsh Cer Forks.
« Reply #266 on: August 28, 2019, 05:25 »
As I said previously "All Ceriani front ends are Harsh".

What might help is fill the triple tree with 5 weight hydraulic oil rather then 10 or 15 weight - Depends on what you're doing with your ride.
« Last Edit: August 28, 2019, 05:29 by Laverda SF »

Online Vince

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Re: Harsh Cer Forks.
« Reply #267 on: August 28, 2019, 05:39 »
The whole point of cartridge forks is there ability to work at absorbing all kinds of bumps i have had emulators work great right out of the box on another bike they just need the right settings mine hopefully are very close

Online Vince

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Re: Harsh Cer Forks.
« Reply #268 on: September 15, 2019, 08:16 »
I have some stuff to add but not till i get my laptop back

Online Vince

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Re: Harsh Cer Forks.
« Reply #269 on: September 20, 2019, 12:29 »
Finally got my laptop back, it only took  8hrs after that to log on to the net. Seems my modem forgot who it was and didn't appear on available wifi. Frustrating when computer says no. So I have been gradually winding back the preload on the emulators down now to the minimum of approx 1 1/2 to 2 turns on the blue spring and its now very compliant. I now can hit those square-edged expansion joints on bridges with no jarring in the bars. I did the last weeks breakfast ride with no memorable fork action on a pretty testing bit of road, pushed it a bit during this. I also fitted the new straight rate shock springs, 2.7kg/mm, to the Icon shocks. I pushed the bump stop down to test travel.  I had a look at how much travel I used by the meeting point, about 60ks of smooth expressway and new dual carriageway and it had used 70mm out of the 90mm available. I then pushed it back down and did the next more testing rougher bit with the same result, that was a bit disappointing so it seems the spring rate was still a bit hard.  New springs do tend to sack out after some use so maybe  I will get this missing 20mm after some time. It will help with luggage on the Tassie ride coming up, although it's still on minimum preload. What I didn't like was the impressively BAD pounding this produced, BANG BANG BANG. Constant and painful. Later I was thinking this feels all spring action, it needed the action slowed, I should have tried dialing up the damping and that's what I did a week later heading to where I got the missing 1st gear issue fixed. Way way better with damping on 2 instead of 1. That's not a full test but at least it looks like an easy fix. The last couple of rides have had the bike steering like it had a hing in the middle, vague wandering steering. I have a well used Bridgestone BT016 on the front, that's a proper sports tire so I expected heaps of grip and no good milage. Approx 3 to 4000ks The grip was ok, not fabulous in the wet though. I had a big front slide once but that was down to me mostly. I pushed it hard into a bend on a ride and the road was wet with me not noticing. This road was made from really black bitumen and there must have been a shower just before we arrived, and the road looked the same as when it was dry. So this tyre had warn in an odd way and I think that's got this instability happening. It had a 20mm flat section in the middle with the sides splayed away in a triangular section. Looked like those triangular race tyres they made in the 70s. So its now got new T31 Bridgestone sports touring front tyre to match the same on the rear. That's the first set of matched tyres its had in 10 years since the old BT090 tyres. Be interesting to see if this fixes the hing effect. Hope to have a well handling comfortable bike for the coming Tassie ride. BTW I went dow to Eibach spring with a spare set of Icon springs off my Laverda and a set of Mazoki springs off my Pantah as he said he might have springs to suit on the shelf, no way. But he did measure the Maz spring off my Pantah. Makes me laugh, the first bit has a good section of spring rate but it then goes to 5.3kg/mm. That's twice as hard as what works, how often do you pillion someone who weights 18 stone.

















« Last Edit: September 20, 2019, 12:41 by Vince »