Review :: RPM G-Plus 2-way shock ...

[abhijitz]

To most guys, riding ability is most important. To me, bike stability and functionality is equally important for average riders like me. I am a very frugal person and do not throw money around, but suspension and jetting/mapping are the 2 biggest things in my books ... Thus, the story begins.

If you are looking for a *rear shock* for your Ninja 250 and you weigh over 160lb and you want to participate in closed circuit competitions, read ahead ...

So, i tried 3 versions of rear shock :

1. gsxr shock (all settings backed out)/stock 9.4kg spring/oem dogbones
2. stock shock with preload at postion #3 and then #4
3. RPM shock with different settings, read on ..

GSXR shock : very difficult to turn the bike with the rear lowered. Absolutely no feeling of rebound. Shock is too stiff. Obviously this shock can be improvised with a refresh, softer spring. But, the biggest issue is ride height ... Only possiblity is : @Rexbo shortened dogbones (not legal in prod races)

Stock shock : WAY BETTER than the GSXR shock, but squats under dip turns, high speed. eg T5 @ Laguna. Absolutely zero compression dampening, rear tire tends to break traction. But, still better.

RPM shock : stock ride height achieved. Preload set at 25mm. rebound set at half (later turned out 2 turns investigating tire wear). rear feels way better under braking, no squating, no breaking sideways. Very smooth transition from full lean to straight.

Mounting the remote reservoir : RPM provides a mount. I drilled the side of the plastic undertray and fitted the reservoir using 2 x metal hose clamps. (see pic below)

Any Improvements that need to be done to the shock? v2?

0. ** V IMP ** --> Provide +5-10mm ride height adjustability capability and then this shock will be golden
1. replace the plastic set screw with brass or include another nut on top of preload adjusters.
2. replace spring to adjuste rspacer spacer from plastic to metal
3. documentation on number of turns. DO's & DONT's (i was about to loosen the screw which held the compression adjustment knob)
4. improvise on the compression dampening knob. too tight for useage. Plus, no clicks.

Overall a great value additon to my bike. IMO, a worthwhile MUST investment on your track/race bike (if you are looking to upgrade the rear shock). You really do not need a Penske or Ohlins to start with. These cost only 340$ via @samw -- Sportisi Motorsport US distributor

Thanks Sam for providing me an oppurtunity to try out the new shock. This has been a great boost to the bike and now i can concentrate more on my riding skills.

My current suspension settings :

Weight with gear : 175lb
Front : 0.80 kg SONIC spring/12.5W oil (stock height)/SSR preload adjust caps
Rear : RPM 2-way GPLUS shock (Race sag 25mm/Preload screw 16 threads OUT/rebound dampening = 14 clicks IN, compression dampening = 1.5 turns IN)
--> New setting 5/7 Thill (Race Sag 28mm/Preload screw 17 threads OUT/rebound dampening = 14 clicks IN, compression dampening = 1.75 turns IN)

All set for AFM Round 2 @ Thunderhill .... Very excited !

[abhijitz]

2012-04-17 12.03.52.jpg

2012-04-17 12.04.42.jpg

2012-04-17 12.04.31.jpg

[abhijitz]

If anyone needs pictures of the shock mounted on the bike, the remote reservoir mount or tire wear, do let me know !

[alex.s]

obviously changes by org but i was under the impression most prod. rules allowed dogbones swaps just not knuckle swaps? now im gonna have to go check cvma rules -_-

[abhijitz]

Nope, not AFM prod. unsure about CVMA or Wera.

Originally Posted by alex.s

obviously changes by org but i was under the impression most prod. rules allowed dogbones swaps just not knuckle swaps? now im gonna have to go check cvma rules -_-

[alex.s]

yeah you are right. legal cvma, illegal afm.

[SPG]

Also illegal WMRRA and OMRRA.

[KazMan]

Very nice write-up Abhijit

I can also testify that this shock does in fact work and is what is installed on the Feel Like a Pro bikes. Last year, I was able to drop 3-4 seconds at Sears Point going from stock to RPM.

Are there improvements about the finish that could be done, YES, as Abhijit points out very nicely.

However, if you are on a budget and looking to get a very workable shock (valving was checked out by several suspension tuners for FLaP) that give you good adjustability, then you may want to give this RPM shot and of course change out the plastic set screws right away.

If the Penske I have now wasn't on the bike when I bought it, I would probably be running one of these as I was able to get it working for me last year.

[Nemesis]

I have an Ohlins which is height adjustable. Works better than any of those.

[abhijitz]

I have Ohlins TTX on my R6, LOVE it. But at this budget price & for this small bike, the shock performs GREAT. If RPM introduces ride height adjustability with a slight price increase, this would be a killer item

Originally Posted by Nemesis

I have an Ohlins which is height adjustable. Works better than any of those.

And, thanks Eric for helping me with the front suspension. I think the bike is well set now and i should concentrate on the tips/lessons you provided at the last trackday and improve myself. Eagerly waiting for AFM R2 @ Thill

[KazMan]

Originally Posted by Nemesis

I have an Ohlins which is height adjustable. Works better than any of those.

oh I'm sorry Nem, perhaps I should have posted something on the 415 chain thread

Figured since I actually used the shock I would write something as it wasn't that bad. But I have been schooled otherwise. My bad

[Nemesis]

Originally Posted by KazMan

oh I'm sorry Nem, perhaps I should have posted something on the 415 chain thread

Figured since I actually used the shock I would write something as it wasn't that bad. But I have been schooled otherwise. My bad

No, I meant I was being an attention whore. Perhaps this pic fits my post.

[KazMan]

Originally Posted by Nemesis

No, I meant I was being an attention whore. Perhaps this pic fits my post.

OHHHHH I get it!

[S.P.Rocket]

I love my Penske shock! Part of the price is that it is specifically made for my weight and riding ability. I have also had a lot of help getting my suspension dailed in by Jeff Kyee, Brandon Kyee's dad.
Which has been awesome since he is roughly my size, but about five seconds faster than me. Eric also has been an awesome help as well learning to articulate what I feel which is incredibly important to get any suspension dialed in.


There is no info on the website for what weight and riding ability the RPM shock is designed for. If I had chosen this shock I probably would have had to buy a different spring and have it revalved since I am on the smaller side. Thus probably ending up costing the same amount for me.

Glad the cheaper option is working for you abijhitz and that Eric helped with the front end!

[abhijitz]

Great input Sarah. The ride height adjustability really makes a difference. I found it when comparing the gsxr shock (which sat lower) and the stock shock.

I had the shock checked by Dave today. Valving is pretty good on this. Per RPM, the current spring is rated ~ 500lb/in ... So, yes you would have needed a softer spring.

As you noted, one of the things that RPM lacks is documentation. I have raised this issue with Sam. If he can take this up with RPM and get in some of the enhancements rolling, this would be one of the best value ad shock

btw - The penske shock costs more than my bike, lol ...

ohh - best of luck on your recovery. eagerly waiting for May 12/13. I had a very good session today with Dave Murphy. Plus, Eric's coaching is helping. T1/T3/T14 much better.

Originally Posted by S.P.Rocket

I love my Penske shock! Part of the price is that it is specifically made for my weight and riding ability. I have also had a lot of help getting my suspension dailed in by Jeff Kyee, Brandon Kyee's dad.
Which has been awesome since he is roughly my size, but about five seconds faster than me. Eric also has been an awesome help as well learning to articulate what I feel which is incredibly important to get any suspension dialed in.


There is no info on the website for what weight and riding ability the RPM shock is designed for. If I had chosen this shock I probably would have had to buy a different spring and have it revalved since I am on the smaller side. Thus probably ending up costing the same amount for me.

Glad the cheaper option is working for you abijhitz and that Eric helped with the front end!

[htdub]

I'm 150lbs, without my gear, would this shock need a softer spring for my weight?

[abhijitz]

Per RPM, this spring is rated from 70kg - 140kg rider weight. But, this spring is 500lb/in progressive. Thats a tad bit stiff for 150lb. I am unsure if the spring can be swapped. Check with @samw@ - Sportisi distributor

Originally Posted by htdub

I'm 150lbs, without my gear, would this shock need a softer spring for my weight?

[htdub]

cool, i'll send samw a message.

[abhijitz]

An update after couple of great trackdays and 2 race weekends (6 podium finishes in novice class).

Shocks works perfect! even at 100+ temperatures. Based on my riding, we tuned in the rear preload and adjusted front ride height.

Thanks to Sam @ Sportisi US for making this affordable product available to us.

[abhijitz]

An update after couple of great trackdays and 2 race weekends (6 podium finishes in novice class).

Shocks works perfect! The awesome Pirelli tires wears nice; even at 100+ temperatures. Based on my riding, we tuned in the rear preload and adjusted front ride height.

Thanks to Sam @ Sportisi US for making this affordable product available to us.

[KazMan]

Originally Posted by abhijitz

An update after couple of great trackdays and 2 race weekends (6 podium finishes in novice class).

Shocks works perfect! The awesome Pirelli tires wears nice; even at 100+ temperatures. Based on my riding, we tuned in the rear preload and adjusted front ride height.

Thanks to Sam @ Sportisi US for making this affordable product available to us.

I just saw that you are a guru!

[abhijitz]

I achieved it being a post whore :rofl ... 250 posts makes anyone a guru, lol

Originally Posted by KazMan

I just saw that you are a guru!

[KazMan]

Originally Posted by abhijitz

I achieved it being a post whore :rofl ... 250 posts makes anyone a guru, lol

ahhhhh I never thought about double posting to get my count up






+1

[tac12345]

Originally Posted by abhijitz

An update after couple of great trackdays and 2 race weekends (6 podium finishes in novice class).

Shocks works perfect! The awesome Pirelli tires wears nice; even at 100+ temperatures. Based on my riding, we tuned in the rear preload and adjusted front ride height.

Thanks to Sam @ Sportisi US for making this affordable product available to us.

what was your last good setup ? i weight about the same as you....
Also, a picture of the shock on your bike would be great

[abhijitz]

umm, my setup will vary from yours based on track/track temperature/tires used. Most of the 250 at Bay Area/NorCal are running the Pirellis. So do I. My suspension is set for the Pirellis

For me, " rider sag" preload is set at 24mm. (+/- 1 turn based on track). Compression dampening at half setting, Rebound dampening at 8 clicks out. [You really need to check your tire wear to verify rebound ie folds on towards the edges facing outwards to verify your rebound]. We also add pressures based on track ambient temperatures to prevent tearing.

I just did my frontend from Jim/Dave Moss @ /Catalyst Reaction Suspension with Jim's custom emulators and now the bike's frontend is so stable. Rebound is controllable.

All i can say is, for 1/3rd the cost of Ohlins or Penske, this shock will give you a head start and is capable of doing decent laptimes. Combine it with the Pirellis and you will be "riding in heaven". I can live without the ride height adjustability for now.

Originally Posted by tac12345

what was your last good setup ? i weight about the same as you....
Also, a picture of the shock on your bike would be great