relay or no relay

[mouse]

I have a motogadget m unit
one of the installation  questions has done me head in lol

http://www.digital-speedos.co.uk/m-unit-v2-881-p.asp

 7.8.1 Important Notes

M-Unit’s Starter Motor Output „start“
Starter motors which coming with solenoid and a solenoid current consumption of maximum 30A
(like Valeo, Bosch, Harley Davidson) can be connected directly to the m-Unit’s „start“ output. In this
case a cable diameter of 2,5mm² has to be applied. All starter motors with external relay (like
Japanese Motorcycles) have to be still powered via the OEM relay. In this case m-Unit’s output
„start“ is connected with the relay which switches the actual cranking current (>100A). Some
Motorcycles have an additional relay to switch the start relay; this second relay is not needed.

I'm going to be using my vw beetle starter motor which has a solenoid fitted it to.
Do I need a separate relay ?  

[morrag]

If the solenoid is of the type that just closes a pair of contacts to supply the starter motor, then its current draw will be of the order of 8/10 A, in which case an auxiliary relay will not be necessary, as long as the push button, or switch contacts used to operate same, are rated accordingly. The 2.5 mm wire will be adequate. If however, the starter motor is of the Pre-Engaged pattern, the draw will be somewhat higher, as the solenoid has to engage a clutch, so I would measure the load to be on the safe side. Morrag

[mouse]

Thanks Morrag
one more question what type of relay would I need

[morrag]

Any relay that has a 12v dc operating coil and at least one pair of Normally Open contacts, rated at 15A as a minimum. Loads on 'E' Bay, and very reasonably priced. Morrag

[mouse]

Thanks Morrag 
Normally open contacts
•30A @ 12V
•Fitted with 30A fuse
•Separate metal bracket

relay or no relay

[morrag]

That will do nicely sir!