Wheel hop!

I hate how bad the wheel hop in my CS is. Just trying to take off even remotely quick results in wheel hop. I never had this in my 99' C2 and it's really irritating. Is this a suspension issue? Suspension geometry issue? Is not having an LSD what's causing this? I've never had a car that did this so I hope there is a fix or solution to this.

Hmmmm..... I've never experienced any wheel hop. But I might be launching differently than you. Or maybe the tires have something to do with it. I have Michellin PS2s. How about you? I remember reading in Car & Track that if they did a clutch drop from 4,000 RPMs they would get a good launch but lots of hop. Is this what you're doing? I've never dropped my clutch, and don't plan to either.

I've tried it a couple times and you get wheel hop with PS2's. I think the reason versus your C2 is there was a lot more weight on the rear tires in that car. These days I have no need for a fast launch , fast through the apex well that's another story.

19" Carrera wheels with PS2's. I never drop the clutch at take-off. I would say I am trying to launch around 2,500-3,000 RPM with a quick clutch release.

Our stock suspensions are a compromise that does not include much concern about how the car behaves during drag strip launches. Wheel hop is the result of the tire moving relative to the chassis and changing the toe angle. You are losing/gaining grip in a viscious cycle as the tread's attack angle changes. You can play with the throttle to limit wheel hop, but you are giving up putting as much power to the ground as you might otherwise be able to. (Ugly sentence nominee 2009) LSD helps but eventually your wheels will hop without suspension changes that might make your car undesirable in other ways. High RPM with LSD will lay down a nice strip of rubber and then hook up and go more smoothly. Imagine your tires are the clutch plate and the ground is...the other thing. LOL. The flywheel? I need more coffee.

I've experienced axel hop on the street and the track. Both times starting from a stop and NOT dropping the clutch... rather a slightly harder clutch engagement and then dropping the hammer. The clutch would be fully engaged and heavy gas applied between 3k-4k rpm. I run PS2's on 19"'s and in both cases the PASM was ON and the Sport Chrono Sport Mode was ON. Can't seem to reproduce without Sport Mode OFF. This is a strong clutch! LOL.

+1. Big time. When I cared about such things as 1/4 mile times & trap speeds Porsche always equalled axle hop, so this doesn't surpise me. Axle hop is so potentially damaging to your vehicle my advice is to avoid it at all costs. It can rip your drivetrain apart. In the dry, get rolling and then nail it in 1st gear. If you want to nail it in the wet get an LSD or a TBD, because I understand even a base Boxster or Cayman may hop just by flooring the throttle in the wet from a rolling start in 1st gear. Dave is right - there's a lot of design subtlety that goes into avoiding axle hop on a launch. I remember reading about GM altering the diameter of one of the rear axles on the ZR1 to avoid a resonance that was causing axle hop. In the old days we just put on a torque arm.

I launch my car hard and fast, but my style doesn't result in any wheel hop.

Fastest cure is to increase tire pressure. It is my experience that root cause is the aft part of the tire contact patch giving up grip before the front of the tire patch. That forward motion of the reaction point causes the torque vector to move in front of the axle which results in an upward force component that compresses the suspension, reduces the load on the tire which spins a little bit until the suspension shoves it back down with enough force to re-adhere to the surface. An LSD will help by limiting the amount of tire spin between adhesions, but will not totally prevent - even a full lock diff. And when you get both tires hopping together, you really know it. And alternating hop will rattle your teeth. I have had wheel hop especially on semi-dry surfaces with both PS2's and Pirelli PZeros 19's. The characterization was not different with the 2 tires . At AX school, I was hopping at 36psi but had no hop at 40 psi. I have also not experienced wheel hop when spinning a tire going around a sharp turn, probably because the tire is unloaded and the contact patch is small from front to back. I think the bottom line is that our suspension is designed for track work, not hole performance. I know darn well that first gear was not ratioed for dragging. You can see the precursor to wheel hop with a big, low pressure slicks under really hard acceleration. Sometimes you can see the sidewall deformation wave going forward from the bottom of the rim to near the tire tread face. I'm sure that in slow motion during a hop, you would see the deformation wave move toward vertical as the tire slips and the axle rises and then reform and slant forward as the tire re-adheres. It is also a function of suspension components and geometry. Back in the day (late 60's, early 70's), we used 50/50 shocks as stiff as we could buy them to prevent hop. I used to joke that I was going to replace my shocks with iron rods and let the hysteresis in the bushings supply the damping. I also would mount my shocks leading the rear axle and that seemed to help. It probably helped less than driver performance factors, but I felt like I was doing something positive.

Hey Kenny, Fascinating explanation of hop - thanks! Please keep sharing the wisdom.

I have had hop issues from the beginning and this is what I have found so far: 1. The amount of hop depends on how warm your tyres are. Cold tyres make it really bad and is one factor you have some small control over. 2. Sure you can do a wimpy takeoff and avoid it. 3. You can dump the clutch and still get it. But if it does it best to back off for reasons already mentioned. 4. My 295mm R spec tyres on the rear did not make it go away. 5. I can do some "number 11s' where both wheels spin in balance and you may or may not still get hop. ie LSD would not have helped in that case. 6. Another Cayman S owner with coilovers gets hop and it seems the problem is more so than mine. 7. The road surface makes a big difference to the amount of hop. 8. I have had some (small) hop powering through corners. Yes, it would be good to get rid of this hop. I can be pretty bad if you let it. In many sporting events we have a standing start and have seen the 997s' do it as well. Anyone with PASM care to comment

A Diff, weather LSD or TBD solves most of the problems relating to wheel hop/tramp as does solid gearbox mounts...

Did we forget something? Tire sidewall plays a role in this too. If you're sitting on 19s, that may be part of the problem. My drag racing buddy advises that more sidewall allows the tire to absorb some of that bounce and dampens the wheel hop.

Yep. You can look at it as a driven damped oscillator. Change the driving function with an LSD or TBD or change the resonant frequency with mounts will change the output. Does anyone with coil overs or higher rate springs or stiffer shocks notice a difference in the characterization of the hop??

I can only relate what just took place with my 06 CS. Ever since I got it, , it would wheel hop in low gear with ease. seemed like nothing I did was right. I talked to my Porsche dealer about it but was basicaly blown off. It then started to even get alittle hard to shift even. It never felt smooth from day 1, but not being a Porsche owner I was not really sure what to expect, so I lived with it. UNTIL this past winter when I would try to take it out of the garage and it would not even shift at all. I had to kill the engine, shift into reverse and then restart to get it out of the garage. After going a 100yeards or so it would snap out of it and shift OK. I told my porsche dealer about this and that if it continues I was going to bring it in (130 miles to dealer) and they were going to find the problem. again they basically blew me off with excuses, mainly my fault excuses. anyway it did it again and again and I finally drove it over to the dealer and told them they could have it for a couple of weeks to test out but to just leave it sit for two days and they will find it will not shift. The very next day they called me and said yes indeed there is something wrong and it has to be clutch related. They took the clutch assembly out and the tech said when he started to pull the clutch even out of the car, he could see that it was in at a bind and not making propler contact. Upon examination the clutch plates showed warping/burn marks where it was sticking etc. The clutch plate and everything looked perfectly new, as the car only had 9000 miles on it and I never drove it hard ever. It to me was my luxury sports car. anyway they said they felt Porsche would give them a hard time warranting this but they would call and talk to them. Well anyways they got it all covered under warranty and I ended up with an entire new clutch assembly including new flywheel,slave cylinder and all the works. UNDER WARRANTY. they told me that in their opinion it left germany that way I had a year left on warranty and had I not got this taken care of I would be afraid to guess what the cost would have been, as this was a real tear down to even get to the clutch,as most of you'se well know. Anyway, I cannot believe just how smooth this Porsche now shifts for me, smooth as butter and NO MORE WHEEL HOPS either. I just love this tranny now but had put up with it for over 3 years not knowing.

Maybe that wasn't wheel hop you were feeling, maybe it was clutch chatter. Glad it's better. Like I said, I launch mine pretty aggressively, sometime with both rear wheels spinning. I almost never experience hop, or none that I wouldn't expect I should say.

That's not wheel hop, that's clutch chatter like Gator Bite mentioned.

I think ur definitely right, now that I think about it, it was clutch chatter... It's sure in hell gone now!!

I use to get horrible wheel hop in my FWD chipped MkV VW GTI. You just couldn't get the power (roughly 245hp) down. The wheels would go hop-hop-hop-hop-hop. One of the main reasons I bought a RWD Cayman was to get into a car that could actually put the power down properly. I only have a Cayman not a Cayman S, but I get no wheel hop off the line and only sometime get a chirp or moment of hop on a hard 1-2 shift. All this talk of hop makes me think my next Cayman may be another base Cayman. Wheel Hop sucks!

You think that's bad, I was being driven around in a proof-testing model of a new 2009 Jag XFR, with the new DFI supercharged 5.0l engine. My colleague works for Jag and one of the things he does is test-pilot their cars for reliability and performance testing. The fact that it was a monster of a car and entirely civilized at the same time was neither here nor there, but by God not once did he put the power down and did I not feel those rears bounce like 36DDs without a sports-bra at trampoline practice. And that's with a high-tech electronic LSD, constantly adjusting magnetic suspension (which unlike PASM can also vary left-to-right), variable sway-bars and custom designed tyres. Having said that it didn't really impede progress, though with that much torque it could lose a wheel and it'd still feel rediculously fast. Going straight, accelerating from 80mph, with opposite lock was an entirely new experience for me.

Bump from the dead. This is my #1 complaint about driving this car. Are there any solutions for this? Stiffer mounts? Suspension bits?

I had a lot of wheel hop from my Good Years when temp was less than 60 degrees under hard acceleration. None from my Michelins yet now that I switched.

I know this is an old post, but: wow! Incredibly informative explanation. Sent from my SAMSUNG -SM-N900A using Tapatalk

I've only experienced hop on semi-wet-dry pavement; and that was at fairly high rev, no LSD . What engine speed are you dropping the clutch at and what type of surface conditions? Sent from my SAMSUNG -SM-N900A using Tapatalk

My biggest complaint too. Mine is on older Michelin PSS. Gets far worse when it is damp and cold. I can even have wheel hop in SECOND gear as the engine gets into it's power band under these conditions. It is easy to avoid by modulating throttle application but I have bad habits coming from a Quattro Audi which just allows you to floor it under most any conditions.

I've posted a lot about wheel hop. You can read my old posts if you like. Suffice to say, yo can fit semi solid transmission mounts, solid bushing LCAs' and solid bushing toe links will fix 80% of it.

Thanks. I know what causes it and how to avoid it but I just miss the ability to use lots of throttle to jump into a gap in traffic from a side street (even in the rain) that my last two Audi 's provided. It is really not THAT big of an issue. Just a bit frustrating. At the track in higher gears and at much higher speeds in corners the Cayman is of course quicker than either and I have never experienced wheel hop there.

I never hard launched my 981 CS, but never had any wheel hop either. It should also be mentioned I hardly ever drive it in the wet or much below 60F. It was a 6 spd manual without PTV and no SC or X73 . It was fairly easy to break the inside tire loose when making a tight turn under heavy or WOT, but NO wheel hop was EVER experienced.

I should also add I experienced this in my 981 Cayman S or in my early Boxster S. I think traction control can do that in most any car in slippery condx.