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Looking to upgrade the track worthiness of the F4, I have a friend who is offering me a very good deal on a slipper clutch but I'm also interested in a ohlins or similar rear shock and I can't decide which to do first. I will likely only be able to slip one or the other past the wife for this season, so what say you guys, should I do the rear suspension first or pop the slipper clutch in?
 

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If you have your suspension set up for the track by a suspension guru, you should be able to get good service out of your stock shock, provided the spring is correctly sized for your weight. If not, it's not expensive to put a bigger spring in the stock rear shock.

Having bounced the rear end of my track bike on heavy braking / downshifts going into corners, I couldn't wait to get a slipper clutch. The slipper clutch and the quickshifter are the #1 and #2 mods I've made to my track bike, after getting the suspension set up correctly, using the right sized rear spring.
 

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Easy answer. If your goal is faster lap times, you must do the suspension. A slipper clutch will not give you lower lap times if the suspension doesn't work for you!
 

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The stock suspension is going to be good enough (if the spring rate is right) to carry you through to A group riding level. Get it set up and you will be good for a while.

Having a slipper clutch was one of the best modifications I ever did to my bike. Now when I am entering turns, the bike is more settled because the rear isn't hopping all over the place. I was able to drop quite a bit of time off of my laps thanks to the less hectic corner entry.
 

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Looking from a different perspective, if your ultimately going to do both mods take the great deal on the clutch it may not be available in the future.
 

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Rear shock.
Put the money into more ride days:f4:
Easy answer. If your goal is faster lap times, you must do the suspension. A slipper clutch will not give you lower lap times if the suspension doesn't work for you!
All of this is great advice and what certainly what I would recommend, even if that slipper clutch is a good price.

The stock suspension is going to be good enough (if the spring rate is right) to carry you through to A group riding level. Get it set up and you will be good for a while.

Having a slipper clutch was one of the best modifications I ever did to my bike. Now when I am entering turns, the bike is more settled because the rear isn't hopping all over the place. I was able to drop quite a bit of time off of my laps thanks to the less hectic corner entry.
On the same bike the OP is talking about ?
 

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Get the shockie Ian........if you don't like it I'll give you a couple of crates of Lion Red for it :)
 

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All of this is great advice and what certainly what I would recommend, even if that slipper clutch is a good price.



On the same bike the OP is talking about ?
No. I'm on an F3. Does his F4 already have a slipper? If so, shock all the way. If not, slipper all the way.

I might be a bit biased because when I got my bike the suspension was already upgraded, and I didn't have a slipper. The addition of a slipper clutch has made riding this bike fast so much easier (in combination with regearing the bike I dropped 6 seconds a lap).

My buddy has an Aprilia Tuono with a Sachs rear shock (I presume the OP's F4 has the same), and he goes pretty fast on it. So that is where my suggestion comes from.
 

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No. I'm on an F3. Does his F4 already have a slipper? If so, shock all the way. If not, slipper all the way.

I might be a bit biased because when I got my bike the suspension was already upgraded, and I didn't have a slipper. The addition of a slipper clutch has made riding this bike fast so much easier (in combination with regearing the bike I dropped 6 seconds a lap).

My buddy has an Aprilia Tuono with a Sachs rear shock (I presume the OP's F4 has the same), and he goes pretty fast on it. So that is where my suggestion comes from.
That would be funny, a Tuono with the same rear shock as a 11 year old MV.
FWIW, to lock the rear wheel on a MY07-07 1000R, you have to pull the revs past the 12 000rpm mark, not many guys do that, that's with fairly decent suspension set-up.

What I was trying to say is, what works on one model is not exactly the same for another model.
The "old" F4 has little or nothing in common with the F3 or a Tuono as far as engine and suspension characteristics are concerned. From experience I've learnt the hard way that you can only push that SACH's so much before it overheats and throws you down the road. I too installed a slipper clutch first, it was cheaper than a new rear shock, but only until I had another costly high-side.
I hope to think I learnt from that.
 

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That would be funny, a Tuono with the same rear shock as a 11 year old MV.
FWIW, to lock the rear wheel on a MY07-07 1000R, you have to pull the revs past the 12 000rpm mark, not many guys do that, that's with fairly decent suspension set-up.

What I was trying to say is, what works on one model is not exactly the same for another model.
The "old" F4 has little or nothing in common with the F3 or a Tuono as far as engine and suspension characteristics are concerned. From experience I've learnt the hard way that you can only push that SACH's so much before it overheats and throws you down the road. I too installed a slipper clutch first, it was cheaper than a new rear shock, but only until I had another costly high-side.
I hope to think I learnt from that.
I was definitely not aware of the nuances of the situation. Yours sounds like the best advice in the thread.
 

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I was definitely not aware of the nuances of the situation. Yours sounds like the best advice in the thread.
Almost all standard shocks (on any brand superbike) will overheat in about 7 laps, so yep the shock is far more important than a slipper clutch
 

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Almost all standard shocks (on any brand superbike) will overheat in about 7 laps...
Do you have a citation to site for this data?

It is my understanding (certainly I could be wrong) that rear shocks heat up their hydraulic systems when set up with excessive rebound damping, poor design, mis-matched spring for rider weight, or poor quality.

I'm having a hard time seeing a novice track day rider on a bike with a properly set up suspension that has a rear spring matched to his weight, heating up a rear shock hydraulic system in 7 laps, but again, I could be missing something.

Please give me some data other than anecdotal examples which may or may not be situations with poorly set up suspension systems or mis-matched springs.

I'm interesting in learning more.
 

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Do you have a citation to site for this data?

It is my understanding (certainly I could be wrong) that rear shocks heat up their hydraulic systems when set up with excessive rebound damping, poor design, mis-matched spring for rider weight, or poor quality.

I'm having a hard time seeing a novice track day rider on a bike with a properly set up suspension that has a rear spring matched to his weight, heating up a rear shock hydraulic system in 7 laps, but again, I could be missing something.

Please give me some data other than anecdotal examples which may or may not be situations with poorly set up suspension systems or mis-matched springs.

I'm interesting in learning more.
Just my experience Kevin...guess it depends how quick you wanna go. Most standard shocks are crap regardless how well you set them up when you really gas it. An example new Honda 1000 with standard suspension and correct spring, set up by so called guru. My mate was lapping at 2.00m odd....I was 20s quicker and the shock was ok for him all day but turned to shit on lap 6 for me...became outright dangerous. This is the only reason that our Sport production championships allow a shock change, purely safety. We put an Ohlins in it, played around a bit to get things right and the CBR was a different animal. Sorry I don't have any data links for you, this is just seat of my pants stuff...but most racers/ex racers feel the same. Next time i speak to our Ohlins guy I will ask him if he has some data/tables to show rates shocks go off, sure he will have, he's a real techo and tests everything
 

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Just my experience Kevin...guess it depends how quick you wanna go. Most standard shocks are crap regardless how well you set them up when you really gas it. An example new Honda 1000 with standard suspension and correct spring, set up by so called guru. My mate was lapping at 2.00m odd....I was 20s quicker and the shock was ok for him all day but turned to shit on lap 6 for me...became outright dangerous. This is the only reason that our Sport production championships allow a shock change, purely safety. We put an Ohlins in it, played around a bit to get things right and the CBR was a different animal. Sorry I don't have any data links for you, this is just seat of my pants stuff...but most racers/ex racers feel the same. Next time i speak to our Ohlins guy I will ask him if he has some data/tables to show rates shocks go off, sure he will have, he's a real techo and tests everything
Yeah, I can't find any data either.

Anecdotally, my Ducati track bike has a Sachs rear shock that is supplied with a spring that is suited for a 140 lb rider (including gear weight). Given that I was 50% heavier at the time, I replaced the spring with one suited for my weight, and had the suspension set up by Ken Hall @ Superbike Suspension, an Ohlins factory trained suspension technician. He reluctantly told me that with the proper sized spring and proper suspension set up, the Sachs would be quite adequate for 20 minute track day sessions, and that the incremental gain in going to a remote reservoir Ohlins would be noticeable but perhaps not terribly significant for an Intermediate track day rider. He said that he sells Ohlins rear shocks to track day riders who mostly have poor quality shocks with either mis-matched springs, or lack of adjustability.

 

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Do you have a citation to site for this data?

It is my understanding (certainly I could be wrong) that rear shocks heat up their hydraulic systems when set up with excessive rebound damping, poor design, mis-matched spring for rider weight, or poor quality.

I'm having a hard time seeing a novice track day rider on a bike with a properly set up suspension that has a rear spring matched to his weight, heating up a rear shock hydraulic system in 7 laps, but again, I could be missing something.

Please give me some data other than anecdotal examples which may or may not be situations with poorly set up suspension systems or mis-matched springs.

I'm interesting in learning more.
Thanks for asking this, I was wondering this too.

So it sounds like if you are as quick around the track as quad-turbo, a new shock is the way to go. Also, how important is a remote reservoir? Is an aftermarket shock without one susceptible to the same problems?

However, if OP is a track day rider lapping a bit slower, would a shock rebuild be adequate? As Donsy pointed out, the shock is 11 years old, so it seems like it is time to do something for the suspension.

@quad-turbo My original thought about the situation was that stock suspension should be adequate for most riders, and your story seems to support this idea. Would your experiences support this as well?
I would be really interested to see that chart as well.

edit: I would also be curious to see data that would show the rate at which the shocks fall off based on rider ability. Do you know if the data set is from a bench or from the track?
 

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Yeah, I can't find any data either.

Anecdotally, my Ducati track bike has a Sachs rear shock that is supplied with a spring that is suited for a 140 lb rider (including gear weight). Given that I was 50% heavier at the time, I replaced the spring with one suited for my weight, and had the suspension set up by Ken Hall @ Superbike Suspension, an Ohlins factory trained suspension technician. He reluctantly told me that with the proper sized spring and proper suspension set up, the Sachs would be quite adequate for 20 minute track day sessions, and that the incremental gain in going to a remote reservoir Ohlins would be noticeable but perhaps not terribly significant for an Intermediate track day rider. He said that he sells Ohlins rear shocks to track day riders who mostly have poor quality shocks with either mis-matched springs, or lack of adjustability.

Thanks for asking this, I was wondering this too.

So it sounds like if you are as quick around the track as quad-turbo, a new shock is the way to go. Also, how important is a remote reservoir? Is an aftermarket shock without one susceptible to the same problems?

However, if OP is a track day rider lapping a bit slower, would a shock rebuild be adequate? As Donsy pointed out, the shock is 11 years old, so it seems like it is time to do something for the suspension.

@quad-turbo My original thought about the situation was that stock suspension should be adequate for most riders, and your story seems to support this idea. Would your experiences support this as well?
I would be really interested to see that chart as well.

edit: I would also be curious to see data that would show the rate at which the shocks fall off based on rider ability. Do you know if the data set is from a bench or from the track?
Kevin, I agree about a track day rider scenario in essence. In reality, my mate that owned the CBR took 10s off his best time within the next 30m session. I took 4s off my time immediately. He felt a lot more comfortable on the Ohlins and was very happy to drop his times. I think any data from our Ohlins guy would be bench data plus 20 years experience in Superbike Racing as a suspension tech. Not sure what onboard telemetry was around in 1995 but nowadays he has equipment at the track to test shocks as the bikes come in.
 

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Dazo, the idea of a remote gas reservoir on a rear shock, as opposed to a piggyback reservoir, is that the remote reservoir can be mounted in the cooler airflow - normally low on the sub frame. This assists in cooling.
The vast majority of shocks supplied are piggyback in design simply because they are cosmetically nicer. You may recall that some 1990s Japanese bikes were sold with remote reservoirs as standard. From memory some of the early 1990s GSXRs for example.

In fact, here is a picture of a 1990s GSXR with the remote reservoir mounted above the exhaust. The reservoir was so ugly that Suzuki painted the bike like a post apocalyptic surfboard to draw the eye away from the abomination that was the remote reservoir.
 

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