Hello everyone
Although I have owned my Radical SR3 since 2011 (The car is a 2007 model with an RS body kit), I am new to the forum and would love to benefit from your experiences. I only need my car for track days.
Now I need to overhaul my 1500cc Gen1 engine and am considering having a spin-save clutch installed. The aim is to prevent damage to the starter and transmission in the event of spins
I have now read the following in a technical bulletin (TB021 001) from Radical:
IN THE EVENT OF A SPIN (With OR Without a Spin-Safe Clutch)
IF the clutch is not depressed and the engine spins backwards, there is a “good” chance that the starter
and opposing gear have been damaged. IF there is any doubt over whether or not this has occurred, DO
NOT start the engine, Call Crown immediately. (Starting or attempting to start the engine could cause
significant damage to the internal workings of the engine)
What does “a good chance” of damage despite the spin-save clutch mean?
Is it worth installing the spin-save clutch in this case?
Thank you very much for your input.
René Widmer
Hi René,
I have two cars and both now have spin safe clutches installed. For track day use they would be fantastic and I would recommend them to anyone. The only thing to take care of is that they need to have their adjustment checked (measured as 'free-play gain' in their instructions) after every couple of hours of use. I normally check mine each day I'm at the track. It doesn't take long once you have the process understood.
I would ignore the comment you quoted about risking damage after a spin with a 'spin-safe' clutch... there is a very low risk of any damage once you understand how these clutches work. The main thing to do during a spin is to get your foot off the throttle and let the engine rpm drop back under around 3000rpm. That's when the Rekluse EXP clutch assembly disengages and opens the clutch plates. If your were silly enough to keep your foot buried in the throttle for too long during your spin, then the engine may not have time to drop it's rpm before the momentum of the car (now going backwards) causes the driveline to run in reverse. A small chance of this happening... but very small in my opinion.
I race my cars and they are a little less suited to that, due to our race series here in Tasmanian including 'standing race starts'. The spin-safe clutch gives reliable/repeatable starts... but they aren't as fast as a manual clutch for race starts... but as I said above, for track days they are perfect.
Thanks, Rod. That makes perfect sense to me.
Another question: a while ago, you were asking about the manufacturer of the SR3 steering rack. Did you find what you were looking for? I need to replace mine.
@rene-widmer … no I didn’t find the OEM… but I did get some details on a ‘service kit’ for them. From memory Josh Smith at RJMotorsports in the UK could get them. I’m away from home right now but could get some details tomorrow if you need more info.
As a new SR3 1500 owner coming from GT cars, one of the first things I did was install a spin safe clutch. I purchased the kit from Rekluse and did the install myself which is a very easy process. I am early in my learning curve with the Radical (I spin on occasion) and the peace of mind with the spin safe is great. I do not worry about jumping on the clutch in a spin and can focus on controlling the car so I don't hit anything or anyone. I think if you will never race, I would run a spin safe all of the time and if you race and never do standing starts, i would still run the spin safe.
I echo Rod's comments about staying on the adjustment which is also very easy once you understand the thinking behind and operation of the clutch.
The only downside is that the car can roll when left in gear because it is not actually in gear when the engine is off. Once you get used to it, its not a big deal just keep wheel choks close and toss them under the wheels as you get out of the car. Yet another benefit of the light weight - it would be a pain with a big heavy car.
Thanks Bryan for your detailed explanations.
Sounds perfect. So I'll definitely get the spin save clutch. It will give me a better feeling.
