2018 Suzuki RMZ450

Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/16/2019 10:01pm
Rotaholic wrote:
Thanks, good video. Best synopsis I've heard yet.
1
SoCalMX70
Posts
2812
Joined
4/1/2008
Location
Thousand Oaks, CA US
8/16/2019 10:57pm
This thread makes me want to get back on a zook... 2019 going for $6k locally.
4
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/16/2019 11:02pm
SoCalMX70 wrote:
This thread makes me want to get back on a zook... 2019 going for $6k locally.
Just ride one and see if it's a fit.
1

The Shop

suspensionguy
Posts
759
Joined
4/23/2018
Location
Bend, OR US
Fantasy
1803rd
8/16/2019 11:28pm
SoCalMX70 wrote:
This thread makes me want to get back on a zook... 2019 going for $6k locally.
$6k new otd?
1
mxb2
Posts
22490
Joined
6/15/2010
Location
Bowie, MD US
8/17/2019 1:10pm
SoCalMX70 wrote:
This thread makes me want to get back on a zook... 2019 going for $6k locally.
$6k new otd?
Yep
1
yz133rider
Posts
4455
Joined
8/1/2013
Location
Avondale, PA US
8/17/2019 7:25pm
Full throttle powersports in NH has amazing deals. Call them.
1
mxb2
Posts
22490
Joined
6/15/2010
Location
Bowie, MD US
8/17/2019 8:16pm
$6k new otd?
mxb2 wrote:
Yep
What dealership?
East coast. Pa,. Ohio,wv. Plenty at the same price. Pay cash outa state
1
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/17/2019 10:24pm Edited Date/Time 8/17/2019 10:26pm
BFRC vs 2017 Suzuki RMZ450 shock.

BFRC 16mm shaft displaces 2.19mm with a 54mm reservior in 25mm stroke (1")

18mm shaft displaces 4.59mm with a 42mm reservoir in 25mm stroke (1")

With 160 psi of nitrogen pressure in both shocks, the BFRC exerts half the pressure the 2017 Showa shock does, effectively bringing down the BFRCs force against the shock shaft to 80 psi. This could explain the wallowy feel, lack of rebound, loose feel and cavitation.

Anyone care to check my calculations?
1
lordworm
Posts
42
Joined
9/8/2018
Location
Hemet, CA US
8/17/2019 10:37pm
Just picked mine up yesterday and started breaking it in today. So far just cruising around it feels good
I'm coming off as 05 yz250.🤙
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/17/2019 10:55pm
lordworm wrote:
Just picked mine up yesterday and started breaking it in today. So far just cruising around it feels good I'm coming off as 05 yz250.🤙[img]https://p.vitalmx.com/photos/forums/2019/08/17/367032/s1200_20190816_160657.jpg[/img]
Just picked mine up yesterday and started breaking it in today. So far just cruising around it feels good
I'm coming off as 05 yz250.🤙
Congratulations! I think you'll love it. Enjoy!
2
TeamGreen
Posts
28657
Joined
11/25/2008
Location
Thru-out, CA US
8/18/2019 4:54am
lordworm wrote:
Just picked mine up yesterday and started breaking it in today. So far just cruising around it feels good I'm coming off as 05 yz250.🤙[img]https://p.vitalmx.com/photos/forums/2019/08/17/367032/s1200_20190816_160657.jpg[/img]
Just picked mine up yesterday and started breaking it in today. So far just cruising around it feels good
I'm coming off as 05 yz250.🤙
Talk about...

"This thread Delivers"!
2
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/19/2019 11:06am
My weekend with the BFRC.

Replaced the check sleeves with my 1mm longer ones which have a total length of 2.88mm

Assembled and bled the shock and felt the compression was MUCH STIFFER than the rebound, and this is backwards. The rebound should ALWAYS feel harder. I don't like changing too many things at once when testing, but made no sense to put the valve cartridge (Adjuster assembly with rebound & compression valves).

Since the shock has way too much low speed compression and way too little rebound across the board, I took 3 of the 34mm x .15 shims off the compression and moved it to the rebound side. This increased the rebound and reduced the compression noticeably. The check valves will no longer be a potential restriction as they were the smallest orifice for the oil to pass to get to the rebound side which I have stated (IIMHO) is starved during big hits.

First pic is the check valve open 2mm.
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/19/2019 11:14am
Stock Valving. MXA did some testing, recommended the rebound 1 turn out instead of Suzuki's setting of 3 turns which was NOTHING.

Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/19/2019 11:22am
Because I like LOTS of adjustment and a shock or fork which is set in the middle, I moved 3 of the 10 34mm x .15 shims to the rebound side. This slowed the rebound and offered some rebound at 3 turns out. This was a simple move. I'd think a 2 stage would ultimately be better on the compression side.

The HUGE reservior reduces the pressure against the shaft during compression. If it were to match the tension of the 18mm shaft on a 2017 Suzuki Showa shock, the pressure would need to be 320 psi which I wouldn't run. Way more surface area with a smaller 16 mm shaft means less force required to overwhelm or compress the bladder at 160 psi.
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/19/2019 11:39am
Last one. Most of you may know this, sharing for gee whiz. This is the flow path from the top down.

1) During compression, oil flows around the check valve, into the compression valve ports
2) Oil flow under pressure opens the compression valve stack and flows into the center chamber
3. Some oil flows through the compression adjuster needle into the center chamber to the reservior, most continues towards the rebound valve
4. Oil continues flowing through the ports in the rebound valve freely which will push the check valve open
5. The pressurized oil flow opens the check valve. If too small it cannot flow to the rebound side of the piston and there is where cavitation can occur, especially high speed hits. I added a longer check sleeve to reduce or eliminate this.

The check opens further so as not to be part of the restriction we want controlled by the valving stack and the needle adjuster. Rebound is upside down the same flow.
2
cody41
Posts
518
Joined
4/25/2013
Location
Miami, FL US
8/19/2019 12:30pm
Does the shock from the previous chassis fit on the 18+? What are the drop in shock options besides the kit shocks, if applicable?
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/19/2019 12:36pm
cody41 wrote:
Does the shock from the previous chassis fit on the 18+? What are the drop in shock options besides the kit shocks, if applicable?
I don't know. You'd think it WOULD as Suzuki is accused of not changing certain things about the bike dimensionally.
Seems that would be a no brainer, going back to 2012 through 2017. But if it were that simple people wouldn't be Frankensteining old Suzuki guts inside WP bodies. This BFRC has so many things dimensionally different than a standard shock it makes it challenging to apply what has worked to this shock.
Rotaholic
Posts
1405
Joined
4/2/2013
Location
NZ
8/19/2019 1:11pm
cody41 wrote:
Does the shock from the previous chassis fit on the 18+? What are the drop in shock options besides the kit shocks, if applicable?
KYB from the 19/20 RMZ250 bolts straight in and is the best option. Ohlins flow is a great bolt in shock. 06 KXF450 shock bolts straight in also.

WP body with 08-17 piston/shaft/clevis works great and is a good option if you don't mind getting your hands dirty.
2
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/19/2019 1:14pm
cody41 wrote:
Does the shock from the previous chassis fit on the 18+? What are the drop in shock options besides the kit shocks, if applicable?
Rotaholic wrote:
KYB from the 19/20 RMZ250 bolts straight in and is the best option. Ohlins flow is a great bolt in shock. 06 KXF450 shock bolts straight...
KYB from the 19/20 RMZ250 bolts straight in and is the best option. Ohlins flow is a great bolt in shock. 06 KXF450 shock bolts straight in also.

WP body with 08-17 piston/shaft/clevis works great and is a good option if you don't mind getting your hands dirty.
I knew if anyone knew you would Wink
MXVet261
Posts
711
Joined
4/1/2008
Location
Valley City, OH US
Fantasy
3973rd
8/19/2019 1:27pm
Sure would be nice to see the internals of the BRFC Kaw was running on Savatgy's bike....

2
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/19/2019 1:32pm
I know.. right? The reservior is smaller and probably works much better because of it. The body looks machined.
1
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/20/2019 9:06am
I'd say that ANYONE who is confident in their mechanic skills should play with their BFRC shock. You WILL LEARN MUCH MORE and get to know your shock. If you send your shock out, you won't know what they did.

If you choose to modify your own BFRC shock, all you need is a bike pump of some kind and a vise with soft jaws.
1) Clamp the shock rod end into your vise
2) Bleed the nitrogen out and push the valving cartridge (the BEST THING about the BFRC Shock) into the shock around 1/8".
3) Pull the circlip.
4) Put a bike pump on the schrader valve and pump slowly to push the valving cartridge out. Won't take much, have a rag and bucket ready below the shock.
5) Use a spray cleaner on the cartridge and/or compressed air
6) Remove the nut and lay out your parts in order on a paper towel or rag
7) Really look at the system and understand how it works.

Revalve: Frankly everything you'll need to make the shock work MUCH BETTER you already have on the valve stacks.As a starter I moved 3 of the 10 34mm shims on the compression valve to the rebound stack. This will slow the whole rebound circuit and really calm down the rear end, it should prove to be dramatic. I'm not exactly sure who sells shims should you want to create your own 2 stage valve stacks but they're out there.

!!!! NOTE !!!! The most DANGEROUS thing about this shock is the circlip for retaining the Valving cartridge. You MUST push the cartridge in beyond the groove for the circlip in the shock body. The cartridge has a groove at the very outer edge which will surround the circlip once you put a little air in the shock. When assembled, the circlip would be impossible to remove because the valve body where the adjuster screws are will be flush with the circlip. If you don't have this seated properly, when you charge the shock it will explode. Once you've bled the shock of all air, charge with 160 psi nitrogen.

This shock can be made awesome, it just needs a little tweaking. I have to ask myself where Suzuki tested this thing to send it with this horrible stock dampening, a sand Supercross track? Way too much compression, way too little rebound. It's a hot mess.
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/20/2019 9:36am
The Circlip will be flush with the shock body once seated. The shock body would make it impossible for the circlip to be removed without first having the cartridge depressed into the shock body first.

colvin227
Posts
431
Joined
8/1/2017
Location
Alamogordo, NM US
8/20/2019 10:53am
Spinazuki wrote:
The Circlip will be flush with the shock body once seated. The shock body would make it impossible for the circlip to be removed without first...
The Circlip will be flush with the shock body once seated. The shock body would make it impossible for the circlip to be removed without first having the cartridge depressed into the shock body first.

Have you got to ride it yet with this valving change?
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/20/2019 11:10am
Nope. Since I decided to revalve it took a day longer. It's charged up and ready to put the spring on and back on the bike. May not get to test it until this weekend. In the pic above, this is the stock valve with the overly stiff compression stack and woefully lacking rebound stack, as well as the 1mm rebound check valve. This is a terrible configuration that can be made better for around $20 in parts made by your local machinist. The stock check sleeve is 1.88mm tall, I went to 2.88mm. Likely all I needed was 2.38mm, 1.5mm travel instead of 2mm travel of the check plate.
Preston412
Posts
883
Joined
10/5/2012
Location
Saint Augustine, FL US
8/25/2019 5:55pm
I tested and tuned my BFRC but it still doesn't touch this beauty.
I have an 08 KYB I used for a little while for sale in the bazaar forum

2
Spinazuki
Posts
79
Joined
8/14/2019
Location
Greenbank, WA US
8/25/2019 6:25pm
That is a beauty. What exactly is it?
3 screw adjusters are low speed, high, what's the 3rd?

Post a reply to: 2018 Suzuki RMZ450

The Latest