Linear Front fork springs

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whyzee79
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Re: Linear Front fork springs

#16 Post by whyzee79 » Sun Feb 14, 2016 5:46 pm

Have you even played with the oil level and air pressure yet? Changing the oil level 5ccs at a time and also changing air 2-4 psi at a time might get you what you are looking for without using different springs.

mike YPVS
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Re: Linear Front fork springs

#17 Post by mike YPVS » Sun Feb 14, 2016 10:01 pm

The simple answer is yes I have played with air pressure, and taken it to the max. No it didn't get me where I wanted to be.

Not much point in changing the oil level on an air adjustable fork as it really does the same thing. Basically I want more spring and less air pressure.

hondaror
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Re: Linear Front fork springs

#18 Post by hondaror » Mon Feb 15, 2016 2:10 pm

I never run air pressure. hard on seals. I'd rather find a set-up that works with oil level, oil weight and spring rate. I hate rebuilding forks. I've recently done 3 sets and I have 7 to go.
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whyzee79
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Re: Linear Front fork springs

#19 Post by whyzee79 » Mon Feb 15, 2016 2:53 pm

The oil can make a big difference in both the viscosity that you use and the amount that is in the fork. As far as the air goes, it came with air caps so it is made to run air. I would start changing just one variable and see what you can do. I suggest keeping the oil viscosity constant and just change the total. The recommendation is that you go up 5ccs at a time but I didn't see much difference until 10ccs. Before getting different springs, just give the oil a try. 10-15wt is a good start. Too much air just makes them rebound harsh. The oil is the dampener along with the spring. If the oil doesn't work for you, then find different springs and start all over adjusting things. That being said, the RZ forks are kind of pathetic and noodley. Oil and air are cheap and might help you out.

mike YPVS
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Re: Linear Front fork springs

#20 Post by mike YPVS » Tue Feb 16, 2016 10:20 pm

Fitted my new springs today, and filled up with motul 12.5. yes I know they don't make a 12.5 but I mixed my own. I previously used 10, but a stronger spring needs more damping. I have not got the bike all back together yet so can't make any comments at the moment.

The problem with the standard springs was that under heavy braking I could run out of travel, I did bump up the air pressure but I don't like loads of pressure in there so opted for stronger springs, I can play about with the air pressure but I would rather it be in the 0 to 8 lbs range than the other extreme.

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JonW
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Re: Linear Front fork springs

#21 Post by JonW » Wed Feb 17, 2016 12:22 am

Mike, FYI just mixing a 50:50 of 10wt and 15wt oils doesnt give 12.5, its a bit more scientific that that sadly. I found that out when researching oils recently. It seems that while we all do/did it, it was an old wives tale :/ It doesnt matter a jot so long as you like the result, and the oil youve made is reproducible if you use the same brand and types, but you cant expect making a mix of one brand to be the same as another you make another time. not dissing your work, just you might not be aware. I did a post on fork oils in the tips section you may fancy a read of, its interesting if youve become interested in fork stuff. :)
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mike YPVS
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Re: Linear Front fork springs

#22 Post by mike YPVS » Wed Feb 17, 2016 9:00 pm

Thanks Jon, Yes I read something about different brand ratings being all over the place. This is why I used the same brand (motul)

What ever it actually is, it is thicker than motul's 10 and thinner than motul's 15 lol . My measurements are not scientific either :smt005

We shall see, when I get it out on the road. The front end is definitely stiffer than it was

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JonW
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Re: Linear Front fork springs

#23 Post by JonW » Wed Feb 17, 2016 9:08 pm

Thats cool Mike, I just didnt want you thinking it could be replicated later with another brand etc. :)

When looking at the tables you can get all sorts of ideas about mixing these to get a value you want, especially for brands and products that are now gone, but i doubt any scientist would approve of our methods LOL!
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
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86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

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mike YPVS
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Re: Linear Front fork springs

#24 Post by mike YPVS » Tue Mar 01, 2016 10:15 pm

Just for anyone who is interested, here are my uprated fork springs. They are fitted now but I have not had the chance to road test them.

Image

These are 30% uprated springs, which is what I am using for starters. They look a lot different, in fact at first I thought they looked too much. It seems that if they had been made from this gauge of wire with the same amount of coils as standard they would have been too strong, adding coils actually softens them. So when I get to test them if I want them stronger, I will get some made with the same gauge wire but fewer coils. Although they look like they will "coil bind" they will actually compress 11 1/2 inch before they become coil bound, and the YPVS only has 5 1/2 inch of travel so no problems there.
Last edited by mike YPVS on Sat Mar 12, 2016 4:28 am, edited 1 time in total.

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wolfman
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Re: Linear Front fork springs

#25 Post by wolfman » Fri Mar 11, 2016 5:48 pm

whyzee79 wrote:The oil can make a big difference in both the viscosity that you use and the amount that is in the fork.
As far as the air goes, it came with air caps so it is made to run air.
I would start changing just one variable and see what you can do. I suggest keeping the oil viscosity constant and just change the total. The recommendation is that you go up 5ccs at a time but I didn't see much difference until 10ccs. Before getting different springs, just give the oil a try. 10-15wt is a good start. Too much air just makes them rebound harsh. The oil is the dampener along with the spring. If the oil doesn't work for you, then find different springs and start all over adjusting things. That being said, the RZ forks are kind of pathetic and noodley. Oil and air are cheap and might help you out.
Not true, these, Imagework well, much better for preload than air.
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mike YPVS
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Re: Linear Front fork springs

#26 Post by mike YPVS » Sat Mar 12, 2016 4:18 am

I wish I could use something like those, but I run with normal type handlebars that sit right above the top of the fork legs. There is no room for them unfortunately.

mike YPVS
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Re: Linear Front fork springs

#27 Post by mike YPVS » Sun Mar 20, 2016 1:02 pm

Well, having now had the chance to put a few miles on the bike with the new springs. I am happy with the result, I really wouldn't want anything firmer than these. I have 30mm of loaded sag, and I am heavy!

chris the rat
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Re: Linear Front fork springs

#28 Post by chris the rat » Tue Mar 22, 2016 2:53 am

Hey mike, would be very interested in a set of those springs. Have also had the problem of bottoming out... No fun..I weight 80 kg. Have a 31k from -83

mike YPVS
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Re: Linear Front fork springs

#29 Post by mike YPVS » Tue Mar 22, 2016 8:37 pm

PM sent

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