The magazine for classic Japanese motorcycles

And, here's what the didn't tell you

Cleaning: Another reason for not cleaning metal floats in heated baths is that they will puncture.

Dismantling: It is far better to fully dismantle a multi carburettor assembly than attempt to clean it as a 'built' multi carburettor unit. Why?

Many carburettors (Keihin VB for example) have diaphragms built into the sides which need dismantling if cleaning is to be thorough. Secondly, the condition of inter carburettor fuel links is a crucial matter which cannot be assessed unless the units are separated. Thirdly, ultrasonics in the form demonstrated is a directional process; the energy coming from transducers in the base of the tank. Full exposure to these cannot be achieved if components are shielded. There are many other reasons.

Costs: When a first class commercial quality ultrasonic clean and rinse can be bought for £20 per carburettor (which includes the cost of return carriage,)
on a 24 hour turnaround, the cost of a tank, at £500 or so, as suggested, is difficult to justify.

Tank size: Small enough to do the job is all that is required. Big tanks cost more to heat, more to chemically treat, more to drain and refill. It is the basket size that dictates whether your cleaning requirements will fit. Plenty of choice on eBay and elsewhere.

Finally: Ultrasonics is not a magic bullet: it is simply a cleaning system and if completed with commercial quality equipment, by experienced staff, is probably the best system currently available. However, a word of caution: 50% or more of JRS carburettor assemblies received for overhaul or restoration have problems other than cleanliness, so do not expect a ‘cleaned’ carburettor assembly to function properly – it may or may not. There is a clear distinction between an ultrasonic cleaning service and an overhaul service which uses ultrasonics to complete the cleaning element. The cost differences reflect that.

Mike
JRS, www.jrs.uk.com