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rhb

Cogent DDC drop in Emulators & Metzeler tires

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rhb
 
The installation of the DDC emulators is literally "drop in" I did fashion a rod with a socket on the end to lower the the valve carefully and to make sure it seated properly. I used a plastic membrane to capture and hold the DDC while I lowered it into the fork. Cogent supplies appropriate grey plastic spacer material which you have to cut to length to arrive at the proper Spring Pre-load. Since I was going to use adjustable preload fork caps, I had some decisions to make. Use the standard MT07 pre-load measurement for the full up position of the adjusters or choose an intermediate point somewhere in between to give me plus and minus adjustment potential. I chose to make the stock pre-load 7 mm down from top out on the adjusters. this gives me at least 10mm more pre-load if I want, and about 8mm less than stock. Its an easy matter to pull the caps with the forks in place if I need to cut more off the spacers later. So after I decided this was my plan, I pulled the first fork apart and redid both forks. DDCs in, I took my front wheel and got the Metzeler Roadtech mounted, brought it home and balanced it on my home made balance rig. I will reassemble tomorrow as time permits.
A note on fork oil. The DDC's are designed to work with a specific brand 5 weight fork oil (Spectro Golden 85/150). They also specify the preferred oil level for each bike.There was no 5W oil anywhere I could find, but I did find 7.5W and 2.5 W Putoline synthetic. So quick math yielded 7.5 + 2.5 = 10 / 2 =5.
This works well at 1/1 ratio, but if you try to use a mathematical model to average oil viscosity in odd percentages, it becomes more complicated.When I got home I cross referenced the Putolene with the brand Cogent recommended and the standard CST viscosity at 40 degrees was higher with the Putolene, but by mixing 50/50 the chemistry worked in my favor and I came within .75 of the desired viscosity. 14.75 CST @40 degrees VS. 14 CST @40 degrees desired. Not bad. There are calculators online that can help with mixing ratios and many viscosity conversion charts also. . It is important to note the W means nothing, some 10W fork oil is equivalent to another companies 20W. You have to go to the charts. To make it worse not all charts online are accurate or a useful tool, Google Transmoto.com.au for an excellent Chart using CST viscosity index.
https://transmoto.com.au/comparative-oil-weights-table/
 
This is a ride review on the Cogent DDC emulators and my Metzeler M7 Sportech RR tires.
Since tires and suspension can both affect your handling, some of the things that I noticed might be due to both and not just one or the other.
 
First the DDC emulators. It's hard to know where to begin, all I can say is this is one of the most profound changes I've made to the bike to date. Around town  the handling of small bumps and Street imperfections is amazing. On twisty Roads I found myself going into Corners at least 10 or 15 kilometers an hour faster. We've all heard the term the front-end Feels planted, well that's exactly how I would describe it. I could actually feel the road and react to road conditions and the bike steered and handled unlike it did before. The bike was easier to ride and comfortable, Eventually, with the addition of a rear shock  this bike will make a great touring machine. At high speed all that floating and uncertainty and head shake was gone. I clocked my highest top speed ever without even knowing it until I glanced down at 180 KPH. I have no experience with cartridge inserts and so I really can't compare to what they might do, but all I can say is that these emulators for the small amount of money they cost did an incredible job of improving the suspension. Really, all I see that you give up over cartridge inserts is an increased amount of adjustability with cartridge inserts. In my case I did add preload adjusters previously, in conjunction with the DDCs they give a nice added adjustability, you can also use oil level to tune the suspension, as well as replacing the springs if required.
My set up was 30mm rider sag, which resulted in a rather small overall travel of about 75mm, I did not force a dive test. So I could probably soften up the pre-load even more if I wanted, but It was so much better I'll leave it alone until I replace the rear shock.
 
Okay now the tires. The change in the new tires was subtle. I don't have enough experience with different kinds of tires to give a concise evaluation. However what I can say is in cornering the tires seem to tip in a lot more easily. In addition with the original Bridgestones, I thought that I had to hold the bike into the corner more, so that was exhibiting what I would call understeer. With the new tires handling was neutral and they tipped in and held the line more precisely. Again a lot of this is subjective and everyone likes a different kind of handling, so it's hard to say exactly what is best for others, but I like the difference. The Metzelers have a slightly higher profile than the old bridgestone's so that would account for their easy tipping in.
 
As far as suspension goes, if you don't need the adjustability of cartridge Forks, or you don't race on the track, the DDC drop-in emulators offer excellent value and do it incredibly good job of improving the front suspension.
 
Just wanted to add the test ride I took was about 360 KM, Cebu to Daanbantayan and back by various routes and road conditions, including wet roads. A long day but exhilarating.
 
Note: in the pictures spring actually goes between the grey plastic spacer and DDC, stacked as shown only to determine pre-load.
What you get from Cogent
IMG_20170620_122737.jpg
 
IMG_20170620_122751.jpg
 
IMG_20170620_122812.jpg
 
IMG_20170624_085608.jpg
insertion tool self made
IMG_20170624_184729.jpg
plastic to capture DDC, held by nut inside socket
IMG_20170624_184808.jpg
properly scrubbed in
IMG_20170627_082525.jpg
75mm normal travel, on the short side
IMG_20170627_082553.jpg
my stack
Inked_IMG_20170624_090604_LI_2.jpg
 
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c0al67
I did the same thing, different brand (traxxion dynamics). It really is a night and day difference on the front end!

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Cruizin
The installation of the DDC emulators is literally "drop in" I did fashion a rod with a socket on the end to lower the the valve carefully and to make sure it seated properly. I used a plastic membrane to capture and hold the DDC while I lowered it into the fork. Cogent supplies appropriate grey plastic spacer material which you have to cut to length to arrive at the proper Spring Pre-load. Since I was going to use adjustable preload fork caps, I had some decisions to make. Use the standard MT07 pre-load measurement for the full up position of the adjusters or choose an intermediate point somewhere in between to give me plus and minus adjustment potential. I chose to make the stock pre-load 7 mm down from top out on the adjusters. this gives me at least 10mm more pre-load if I want, and about 8mm less than stock. Its an easy matter to pull the caps with the forks in place if I need to cut more off the spacers later. So after I decided this was my plan, I pulled the first fork apart and redid both forks. DDCs in, I took my front wheel and got the Metzeler Roadtech mounted, brought it home and balanced it on my home made balance rig. I will reassemble tomorrow as time permits.
A note on fork oil. The DDC's are designed to work with a specific brand 5 weight fork oil (Spectro Golden 85/150). They also specify the preferred oil level for each bike.There was no 5W oil anywhere I could find, but I did find 7.5W and 2.5 W Putoline synthetic. So quick math yielded 7.5 + 2.5 = 10 / 2 =5.
This works well at 1/1 ratio, but if you try to use a mathematical model to average oil viscosity in odd percentages, it becomes more complicated.When I got home I cross referenced the Putolene with the brand Cogent recommended and the standard CST viscosity at 40 degrees was higher with the Putolene, but by mixing 50/50 the chemistry worked in my favor and I came within .75 of the desired viscosity. 14.75 CST @40 degrees VS. 14 CST @40 degrees desired. Not bad. There are calculators online that can help with mixing ratios and many viscosity conversion charts also. . It is important to note the W means nothing, some 10W fork oil is equivalent to another companies 20W. You have to go to the charts. To make it worse not all charts online are accurate or a useful tool, Google Transmoto.com.au for an excellent Chart using CST viscosity index.
https://transmoto.com.au/comparative-oil-weights-table/
 
This is a ride review on the Cogent DDC emulators and my Metzeler M7 Sportech RR tires.
Since tires and suspension can both affect your handling, some of the things that I noticed might be due to both and not just one or the other.
 
First the DDC emulators. It's hard to know where to begin, all I can say is this is one of the most profound changes I've made to the bike to date. Around town  the handling of small bumps and Street imperfections is amazing. On twisty Roads I found myself going into Corners at least 10 or 15 kilometers an hour faster. We've all heard the term the front-end Feels planted, well that's exactly how I would describe it. I could actually feel the road and react to road conditions and the bike steered and handled unlike it did before. The bike was easier to ride and comfortable, Eventually, with the addition of a rear shock  this bike will make a great touring machine. At high speed all that floating and uncertainty and head shake was gone. I clocked my highest top speed ever without even knowing it until I glanced down at 180 KPH. I have no experience with cartridge inserts and so I really can't compare to what they might do, but all I can say is that these emulators for the small amount of money they cost did an incredible job of improving the suspension. Really, all I see that you give up over cartridge inserts is an increased amount of adjustability with cartridge inserts. In my case I did add preload adjusters previously, in conjunction with the DDCs they give a nice added adjustability, you can also use oil level to tune the suspension, as well as replacing the springs if required.
My set up was 30mm rider sag, which resulted in a rather small overall travel of about 75mm, I did not force a dive test. So I could probably soften up the pre-load even more if I wanted, but It was so much better I'll leave it alone until I replace the rear shock.
 
Okay now the tires. The change in the new tires was subtle. I don't have enough experience with different kinds of tires to give a concise evaluation. However what I can say is in cornering the tires seem to tip in a lot more easily. In addition with the original Bridgestones, I thought that I had to hold the bike into the corner more, so that was exhibiting what I would call understeer. With the new tires handling was neutral and they tipped in and held the line more precisely. Again a lot of this is subjective and everyone likes a different kind of handling, so it's hard to say exactly what is best for others, but I like the difference. The Metzelers have a slightly higher profile than the old bridgestone's so that would account for their easy tipping in.
 
As far as suspension goes, if you don't need the adjustability of cartridge Forks, or you don't race on the track, the DDC drop-in emulators offer excellent value and do it incredibly good job of improving the front suspension.
 
Just wanted to add the test ride I took was about 360 KM, Cebu to Daanbantayan and back by various routes and road conditions, including wet roads. A long day but exhilarating.
 
Note: in the pictures spring actually goes between the grey plastic spacer and DDC, stacked as shown only to determine pre-load.
What you get from Cogent
IMG_20170620_122737.jpg
 
IMG_20170620_122751.jpg
 
IMG_20170620_122812.jpg
 
IMG_20170624_085608.jpg
insertion tool self made
IMG_20170624_184729.jpg
plastic to capture DDC, held by nut inside socket
IMG_20170624_184808.jpg
properly scrubbed in
IMG_20170627_082525.jpg
75mm normal travel, on the short side
IMG_20170627_082553.jpg
my stack
Inked_IMG_20170624_090604_LI_2.jpg

 
Cogent is a supporting vendor on our FJ-09 forum and Im trying to get hem on board here too!

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pattonme
> Golden Spectro Cartridge Fork (85/150, Race Tech RSF05)
 
Is also known as Race Tech RSF05, but any oil in the neighborhood of 16cSt@40 will work.
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faffi
Silikolene 2.5W is 13.6cSt if you want to go a little lighter for more comfort. If you want more feedback, around 18-19cSt will work better, but will give a noticeably firmer ride. 16cSt is probably the safest compromise.

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Beemer
So what do you like to use to scrub them new tires?
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rhb
So what do you like to use to scrub them new tires?
Asphalt @ 58 degrees lean < 
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avanti
I give up, what is the wooden wall-rack for that the installer is shown on/against? Thanks.

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rhb
I give up, what is the wooden wall-rack for that the installer is shown on/against? Thanks.
not a wall rack, but my home made saw horses. From Philippine Luan mahogany 
saw_horses.jpg
 
very handy forvarious tasks.
 
 
IMG_20170612_103410.jpg
 
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avanti
Thank YOU, rhb... my education is now complete and I'll not have to return my Ph.D.
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