Building an RTS clutch - Photo Heavy
Turbo Mini Forums

Now I know that there is a thread on here, named “clutch thoughts” by Robert. And he is the true inventor of this!

But for the likes of stupid people like me, whilst I was building my RTS clutch assembly I took photos of every stage and thought that it may be of some use to those stupid people (like me) who may like to know exactly what it entails.

So for the people who don’t know what an RTS is; it is a verto clutch assembly that uses two diaphragms/spring instead of one. Why the verto? The more torque/power your engine produces the higher the clamping pressure you need on the friction plate. With well over 200bhp now being the norm, grey and double grey pre verto set-ups were being used. Its all well and good using a pre-verto with a double grey, but they eat thrust bearings for breakfast. But if you wanted big power you had no choice. Until Robert came up with the verto RTS. The verto clutch system doesn’t load the thrust bearings anywhere near what the pre-verto did.

The original thread is here http://www.turbominis.co.uk/forums/index.php?p=vt&tid=10207

I am building an engine that will hopefully produce good results (170bhp+) and wanted to fit an RTS to said engine….

List of parts required;
2 verto clutch/flywheel assemblies of your choice (different diaphragm thicknesses produce different clamping pressures)
Decent friction plate
New spacers x 9
High tensile alan head bolts x 9 for the diaphragms
High tensile alan head bolts x 6 for the flywheel (upgraded from original)


Building the assembly

First thing of all was to take the two assemblies to pieces.



They are held together with 9 soft metal rivets. You need to drill out the rivets accurately. I did this by using a centre punch and marking the centre of the top of the rivet. Then using a suitable size drill bit, drill into the centre and remove the head of the rivet. Once all nine have been drilled out the support ring will come free



and reveal the first of the pivot rings.



Now depending on the assemblies you have chosen you could have a solid pivot ring or a pivot ring with a break in it and location pins. I had a turbo (solid ring) and a standard metro (broken with location pins) assembly.

Remove the ring and place safely to one side. You should now be able to remove the spring. Depending of which of the two assemblies you will be using you can carry on disassembling it or put it to one side and start taking the next one to bits.

With the spring removed you can see the nine spacers, I had to drill down into the centre in order to release them.



Measured the centre and used a bit slightly smaller than the hole. Once I’d drilled far enough they just popped off.





Now you need to punch the rest of the rivet out through the back of the plate. I had to insert a screwdriver in order to create enough of a gap to punch the rivet through.



With all the rivets out you need to measure up for the new spacers. You need to measure both springs very accurately and make a note of it. You’ll also need to know the length of the spacers that were in the in the plate that you’ll be using. The new spacers need to be the length of the originals plus the thickness of the additional spring. Joe C made these a whole ago and he was kind enough to make a set for me too. You could easily get a local machinist to make some up for you.

Next step is to tap the holes left by the rivets. You’ll need a good quality M8x1.25 tap to do this. Don’t be tempted to buy cheap shite for this, the hole is slightly undersize for an M8 tap (normally 6.8mm, the hole here is 6.4mm) so it’s a tight fit.





With the nine holes tapped I put the plate in my parts washer and cleaned it. There was a lot of swarf left from drilling and tapping.

I was advised that it’s best to lightly polish the two surfaces of the springs that are going to touch. So I did using 400 grit wet and dry. It was also advised to colour in those surfaces with a pencil to reduce friction whilst in use.





So that done you can start the reassembly process…

Pivot ring on, take the two springs and position them on the plate making sure you align the three holes for the pullers. Slide in the new spacers – these were quite tight for me, I had to dress them slightly to fit.



With those in the top pivot ring goes on. I took a picture with it on to show how it fits.



I used the original top ring and not washers. With the top support ring on over the top pivot ring you fit the bolts. I found it easier to slide in something to push the plate closer making it easier to fit the bolts. With all the bolts in I took one out at a time a thread locked them in with Loctite 270.
And that’s it, not all that difficult but you need to have use of some good quality tools in order that it gets completed successfully.



I hope that this makes it easier for people to see how simple the RTS really is.
If you use this as a guide, I accept no responsibility for damages of any kind to you or any other no matter how caused.

Good write up fella!

If something is worth doing, it's worth doing half of.

nice, this come in very handy....
can/should this be topped?

Jack Jones

I will be using this write up very soon excellent job

Andy

Excellent, thank you :)

Pedro Silva

http://miniciados.blogspot.pt/

possibly a silly question but what was the length of the bolts used? or what would be best to use and trim to size

"Tuning should be a compromise between what is possible and what is necessary"

10)Thou shalt always quest for more power

180mm or 190mm parts used ?

topped it, very nice and useful write up chap! :)

Great info
Defo not confident enough to do it though haha

Reading up on RTS Clutches

Oh just found it

Oh just found it

will any body supply me the bolts washers and spacers

I have done these in the past but have got through all the ones I had,

thers nothing clever about the bits, you need 9x M8x20 capheads, and some 11mm bar drilled to m8 clearance then cut to suite.

the tricky bit is getting all the spacers the same length but this can be done by sticking them in a drill and using a file. try to get them within 0.1mm of each other.

this seems very simple, when i have a go at it, im thinking of making extra spacers for other people, but since i read that there are a lot of variants in springs im wondering if its worth doing as they may end up being the wrong length?

I had a load of spacers made (14mm iirc) then trimmed them to suit each application.

seems a good idea, mild steel or stainless? seen some stainless tube on ebay 11mm OD and 7mm ID seems ideal if i drill out the center

stainless can be a pita to work withas it goes hard if you get it hot so i'd go with the mild

This thread is outdated ......................

Is there an updated one?

Sorry for being completely ignorant to this- but is it basically a verto clutch with 2 springs sandwiched together?

And apart from dealing with lots of torque, are there any other benefits over pre-verto on NA torque levels etc?

www.topcatcustom.co.uk

yep, 2 springs wedged onto a verto,

on the non verto you get the full pressure of the clutch against the thrusts (about 1100lb for a grey)

for an rts or about 1500lb clamping pressure you end up with about 750lb on the thrusts, similar to a cooper S spring.

What is the actual size of the bolts? 9 M8x20 and 6 M10x what?

What is outdated about this thread? It doesn't like in the photos this guy was using washers on the diaphragms. Are these not necessary anymore?

M8x20, and M8x15 for the others, athough I think the 20' are ok for all of them.

dont use washers (the m8x20's will be too short if you do), just use the pressed ring that comes with the clutch.

Great! Do they need to be high tensile? I could get some 12.9's if so.
Did you say you used about 14mm spacers and trimmed to suit joe?

Yes i moved to the darkside

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