GP Suspension 25mm Cartridge Kit + Ohlins YA 537 Shock

[mbassani]

Hey all, 

 

So I bought a 2019 Tracer 900 (Non-GT) new for a stupid deal I couldn't say no to. 

My background is in track riding and racing so the stock suspension left me extremely wanting. For comparison my track bike is on Öhlins pressurized forks and a TTX36 rear. 

 

After the first track day this year since COVID I connected with a race shop that does suspension tuning at the track, they happened to have a YA 537 with a 1.00 spring in stock that I got for a pretty great deal. I rode on the stock forks and Öhlins rear for a few weeks before it became extremely apparent how weak the front suspension is on the Tracer 900. Fortunately for me GP Suspension located in California is about 10 minutes from where I live and earlier in the year they rebuilt the suspension for my track bike. I brought my Tracer to them and instead of ordering the Öhlins NIX 30 cartridge kit I decided to give their front cartridge kit a try. 

 

I just got the bike back and the different is fairly astonishing. I also had 1.00 springs installed in the forks. While the stock suspension would dive fairly deep into the stroke under moderate to hard braking the 25mm Cartridges keep the bike far more under control while under braking, the valving keeps the forks far closer to the middle of the stroke so even braking under rough roads does not upset the chassis like the stock suspension did. For my street bikes I tend to aim for 28-30mm of sag and got the Tracer set at 30mm very easily with some help from the tech at GP. 

 

Likewise setting my rebound was very easy, thankfully you can set a very solid baseline rebound on a bike standing still, compression takes a little more trial and error while riding. 

 

The stock suspension is fine for a budget piece of kit but the shared compression and rebound functions in the right fork leg really end up compromising both and leaves the left leg as a dummy with a spring and fluid only. 

 

All in all I am pretty crazy about the setup of the GP Cartridges and Öhlins shock and I would recommend it to anyone considering suspension for their Tracer. 

 

If you have any question let me know and I'll do my best to answer them. 

 

 

[mbassani]

[betoney]

1 hour ago, mbassani said:

Fortunately for me GP Suspension located in California is about 10 minutes from where I live and earlier in the year they rebuilt the suspension for my track bike. I brought my Tracer to them and instead of ordering the Öhlins NIX 30 cartridge kit I decided to give their front cartridge kit a try. 

I just got the bike back and the different is fairly astonishing. I also had 1.00 springs installed in the forks. While the stock suspension would dive fairly deep into the stroke under moderate to hard braking the 25mm Cartridges keep the bike far more under control while under braking, the valving keeps the forks far closer to the middle of the stroke so even braking under rough roads does not upset the chassis like the stock suspension did. For my street bikes I tend to aim for 28-30mm of sag and got the Tracer set at 30mm very easily with some help from the tech at GP.

All in all I am pretty crazy about the setup of the GP Cartridges and Öhlins shock and I would recommend it to anyone considering suspension for their Tracer.

If you have any question let me know and I'll do my best to answer them.

Nice setup you have there, it sounds like it is a beautiful ride now.

Prior to the GP cartridges had you done any upgrades to the forks?  I currently have a Penske shock from Traxxion Dynamics and modified stock cartridges, - the dead leg fitted with a modified active cartridge.  Even though the ride is drastically improved I always wonder if it can be better and if the GP cartridges would perform any better than modified factory forks.

Suspension is one thing that I don't mind spending money on, every bike in past 25 years has had custom setup suspension, just wondering how the GP setup might be an improvement on the modified factory forks, I have never had custom built drop-in cartridges. 

 

[mbassani]

1 hour ago, betoney said:

Nice setup you have there, it sounds like it is a beautiful ride now.

Prior to the GP cartridges had you done any upgrades to the forks?  I currently have a Penske shock from Traxxion Dynamics and modified stock cartridges, - the dead leg fitted with a modified active cartridge.  Even though the ride is drastically improved I always wonder if it can be better and if the GP cartridges would perform any better than modified factory forks.

Suspension is one thing that I don't mind spending money on, every bike in past 25 years has had custom setup suspension, just wondering how the GP setup might be an improvement on the modified factory forks, I have never had custom built drop-in cartridges. 

 

Funny you ask, I actually had the re-valve kit from GP Suspension put in prior to me changing my mind and deciding to go for the full cartridge kit. 

So the active fork went from rebound only to compression and rebound sharing an adjuster. So you could only stiffen or soften damping in both directions. I was actually fairly impressed with the setup all things considered but the big issue for me was the dive under braking and performance under spirited riding. The ride was compliant and comfortable at highway speeds and if commuting was the only thing I did on the bike I would have been satisfied. 

 

I have maybe 60 miles with the cartridges since I picked the bike up earlier today and I had a chance to take it around a canyon road and do some maximum braking tests. The difference is extremely apparent, the high speed compression is less abrupt. For example when running over the reflective markers on the highway with the stock or revalve kit I was able to feel the impact through the entire chassis. On the Cartridge kit I had to run over 3-4 in a row to notice the bumps at all. There is one quirk I need more time to figure out but I believe the cartridge kit has less overall mass than the revalve or OEM setup. The front end feel is lighter and it turns far faster now, I need more time to ride and figure out exactly what is different. 

Remarkable improvement in comfort on the highway and it doesn't fall apart once I go for a spirited ride. If I needed forks for my CBR I have no doubt I would buy these over the NIX 30 at a similar price point. 

[betoney]

14 minutes ago, mbassani said:

Funny you ask, I actually had the re-valve kit from GP Suspension put in prior to me changing my mind and deciding to go for the full cartridge kit. 

So the active fork went from rebound only to compression and rebound sharing an adjuster. So you could only stiffen or soften damping in both directions. I was actually fairly impressed with the setup all things considered but the big issue for me was the dive under braking and performance under spirited riding. The ride was compliant and comfortable at highway speeds and if commuting was the only thing I did on the bike I would have been satisfied. 

 

I have maybe 60 miles with the cartridges since I picked the bike up earlier today and I had a chance to take it around a canyon road and do some maximum braking tests. The difference is extremely apparent, the high speed compression is less abrupt. For example when running over the reflective markers on the highway with the stock or revalve kit I was able to feel the impact through the entire chassis. On the Cartridge kit I had to run over 3-4 in a row to notice the bumps at all. There is one quirk I need more time to figure out but I believe the cartridge kit has less overall mass than the revalve or OEM setup. The front end feel is lighter and it turns far faster now, I need more time to ride and figure out exactly what is different. 

Remarkable improvement in comfort on the highway and it doesn't fall apart once I go for a spirited ride. If I needed forks for my CBR I have no doubt I would buy these over the NIX 30 at a similar price point. 

Thanks for the detailed info.  There is a great suspension shop about an hour away from me who happen to build GP Suspension cartridges.  I'll have to chat with the techs and see what they recommend, my suspension is due for servicing during the winter down time.  I'm really happy with the Penske from Traxxion Dynamics so may give some thought to their AK-20's as well.

[texscottyd]

Great info @mbassani - thanks for taking the time to document this.  

I'm debating taking another step up with the suspension on my FJ, so this is very timely.   I have an Ohlins 535 on mine, and did the RaceTech springs & gold valves on the factory forks.   While it's a huge improvement from stock, the front is still a little shy of what I ultimately would like to have...  in retrospect, if I had known how well the bike could work with upgraded suspension, I would have just gone straight to the NIX 30 the first time.   I have AK20s in my 636 track bike (with a Penske triple shock), and Ohlins forks on my Aprilia, and the RaceTech setup on the FJ is comparatively about an 85% solution.  

So, now I'm looking at the next level options.  This GP Suspension cartridge set up sounds very temping, so I'll add it to the list to investigate, along with the Ohlins cartridge & AK-20 route.  

Out of curiosity, what are you running for tires?   I recently made the swap from Michelin PR5s to Dunlop RoadSmart IIIs, and am chasing the setup just a bit... 

[BBB]

1 minute ago, texscottyd said:

 This GP Suspension cartridge set up sounds very temping, so I'll add it to the list to investigate, along with the Ohlins cartridge & AK-20 route.  

I love the euphemism “investigate” @texscottyd when we all know it means “I already have all the options in my basket and just can’t decide when to press the buy now button”.

Do you wait until the second/third/fourth beer, the rest of the household is in bed, decisions seem so clear at 1am? Your browser has already entered your credit card details and you just need to enter the CVC code? 

[texscottyd]

1 hour ago, BBB said:

I love the euphemism “investigate” @texscottyd when we all know it means “I already have all the options in my basket and just can’t decide when to press the buy now button”.

Do you wait until the second/third/fourth beer, the rest of the household is in bed, decisions seem so clear at 1am? Your browser has already entered your credit card details and you just need to enter the CVC code? 

Ha!  Your assessment falls into the category I like to call “not entirely untrue”   

The real conundrum is that I also have a 2020 KTM 890 Duke R in the cart.   I need to hurry up and sell some stuff, actually...  anyone interested in a really clean Aprilia Mille R, or a nice track-prepped Kawasaki 636?   Wife rightfully insists that something has to go before something new arrives...  

[mbassani]

3 hours ago, texscottyd said:

Great info @mbassani - thanks for taking the time to document this.  

I'm debating taking another step up with the suspension on my FJ, so this is very timely.   I have an Ohlins 535 on mine, and did the RaceTech springs & gold valves on the factory forks.   While it's a huge improvement from stock, the front is still a little shy of what I ultimately would like to have...  in retrospect, if I had known how well the bike could work with upgraded suspension, I would have just gone straight to the NIX 30 the first time.   I have AK20s in my 636 track bike (with a Penske triple shock), and Ohlins forks on my Aprilia, and the RaceTech setup on the FJ is comparatively about an 85% solution.  

So, now I'm looking at the next level options.  This GP Suspension cartridge set up sounds very temping, so I'll add it to the list to investigate, along with the Ohlins cartridge & AK-20 route.  

Out of curiosity, what are you running for tires?   I recently made the swap from Michelin PR5s to Dunlop RoadSmart IIIs, and am chasing the setup just a bit... 

Don't knock the Racetech Gold Valve setup, my track bike was on that before I got the pressurized Öhlins and they were unbelievable performance for the price. 

 

I am currently running Michelin Road 5 tires in the OEM size. 

 

 

2 hours ago, texscottyd said:

Ha!  Your assessment falls into the category I like to call “not entirely untrue”   

The real conundrum is that I also have a 2020 KTM 890 Duke R in the cart.   I need to hurry up and sell some stuff, actually...  anyone interested in a really clean Aprilia Mille R, or a nice track-prepped Kawasaki 636?   Wife rightfully insists that something has to go before something new arrives...  

My girlfriend is giving me much the same talk. I am prepping my Tracer 900 for long distance tours and I have already taken it on one. Once I got back I thought man I should buy a GS for long distance rides and keep the Tracer for commuting.

[texscottyd]

19 hours ago, mbassani said:

Don't knock the Racetech Gold Valve setup, my track bike was on that before I got the pressurized Öhlins and they were unbelievable performance for the price.

I am currently running Michelin Road 5 tires in the OEM size.

I totally agree that the RaceTech Gold Valves are a huge upgrade, especially at the price point.  I've got about 15,000 miles on this set up, and have been very pleased.   But...  the recovering racer in me still wants just a little bit more.  The tactile feedback - especially over repetitive sharp-edge bumps when carrying some lean angle - still feels just a bit wooden.   Without the ability to fine tune compression independent from rebound (a product of the stock fork design limitation) I'm still playing with the best compromise.   Interestingly, what was working with the Road 5 isn't working as well with the RS3...   The edge grip is great, but the steering feedback is muted.   I'll play around with it a bit more this weekend (weather permitting) to see if I can get back to the sweet spot...  or as sweet of a spot as I can with the current set up. 

Or maybe I'm just a vain poser, and really want those bad-ass looking adjuster caps on my forks...     

[BBB]

15 hours ago, texscottyd said:

The edge grip is great, but the steering feedback is muted. 

Could this be a tyre pressure problem @texscottyd?

[betoney]

6 hours ago, BBB said:

Could this be a tyre pressure problem @texscottyd?

Well that's no fun, you cant add 'air pressure' to your cart, or get shipping confirmation... just sayin' 🤷‍♀️

[texscottyd]

25 minutes ago, betoney said:

Well that's no fun, you cant add 'air pressure' to your cart, or get shipping confirmation... just sayin' 🤷‍♀️

You’ve clearly never seen my wife’s Amazon Prime purchase history!   😳

@BBB - I’ve tried from 30 to 36 pounds (that’s lbs/inch^2 using our mesmerizing US system of weights and measures), with no discernible difference.  I’m convinced it’s the overall profile of the front Dunlop RS3 vs the Michelin Road 5:   I think the Dunlop is a rounder profile, so the steering feels very light (almost too light, truthfully) and linear, but it doesn’t feel like it gets the same ‘set’ as the Michelin out near the edge.  The tactile feedback just isn’t as clear and direct to me...  I think lowering the front just a bit more may help, since the Dunlop feels noticeably taller than the Michelin.  I’m surprised at just how different the tires feel... not better or worse, just very different.   I’ll start another thread with some more details, observations, and setup findings. 

[koth442]

1 hour ago, texscottyd said:

I’ve tried from 30 to 36 pounds (that’s lbs/inch^2 using our mesmerizing US system of weights and measures)

That actually brings up a good question, @BBB or anyone else not in the US, what unit of pressure do you use?

kPa? bar?

[BBB]

3 hours ago, koth442 said:

That actually brings up a good question, @BBB or anyone else not in the US, what unit of pressure do you use?

kPa? bar?

For most tyres it’s psi, as that’s what’s written on the underside of our bikes, or on the info card inside the drivers door on the car, or even on the sidewall of my mountain bike tyres. Except my 535D, which insists on bar, for some Germanic logic.

In school  all pressures are kPa.