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Old 31 July 2010, 19:09   #21
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Country: UK - Channel Islands
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Boat name: Martini II
Make: Arctic 28/FC470
Length: 8m +
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Originally Posted by chewy View Post
On the plus side having two engines you can swap parts till you find whats at fault.
Another advantage of twins, I've saved an absolute fortune on parts that I didn't need by doing this!

This one wasn't too difficult to figure out, took a couple of hours. Being an intermittent fault it's nearly always down to bad connections, supply from ignition switch was ok, ruled out kill switch, main power relay working (you can hear it), fuses ok. Wiggled around all the wiring under the hood and behind console made no difference inc. the cps harness. Then I tapped the cps with a 1/4" extension while the motor was running and it stopped dead! Did it a few times to confirm, job done!

Hopefully a new one will be fitted for another trip up to Alderney next weekend for Alderney Week. Have you thought about going this year Keith?

ps apologies for the highjack
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Old 31 July 2010, 19:17   #22
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Another advantage of twins, I've saved an absolute fortune on parts that I didn't need by doing this!

This one wasn't too difficult to figure out, took a couple of hours. Being an intermittent fault it's nearly always down to bad connections, supply from ignition switch was ok, ruled out kill switch, main power relay working (you can hear it), fuses ok. Wiggled around all the wiring under the hood and behind console made no difference inc. the cps harness. Then I tapped the cps with a 1/4" extension while the motor was running and it stopped dead! Did it a few times to confirm, job done!

Hopefully a new one will be fitted for another trip up to Alderney next weekend for Alderney Week. Have you thought about going this year Keith?

ps apologies for the highjack

All the posts like this help many thanks still banging my head
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Old 31 July 2010, 20:03   #23
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Trial an option?

Maybe.. if you are realy THAT undecided a sea trial with both setups would be a good idea, it may well help your final choice.I'm sure the guys at Ribcraft could arange it,or put you in touch with previous customers[who can also give you the benifit of thier experiance] ,maybe even forum memebers may be able to help.
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Old 31 July 2010, 20:26   #24
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Country: UK - Channel Islands
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Hopefully a new one will be fitted for another trip up to Alderney next weekend for Alderney Week. Have you thought about going this year Keith?

ps apologies for the highjack
May do. See what the weather's like towards the end of the week. Double apologies for the hi-jack
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Old 01 August 2010, 00:11   #25
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Dont want to start full debate again twin 90s or single 225 , twins giving about 40 knots single 46knots but then will have to look at a aux i really can not make my mind up on this

I would go for the 225 and an aux. The only time I have found twins to be of great value (apart from the slightly better get-you-home speed) is if you do a lot of close quarter maneuvering, otherwise one big one will always be more fun that two little ones - or so I've been told.
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Old 02 August 2010, 11:53   #26
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Country: UK - Scotland
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Originally Posted by Carl View Post
plus all that extra drag

In summary drag goes up as approx the square of your speed and the cube of the cross sectional area of what you're dragging through the water.

I'll bet the 90s have a substantially smaller gearbox than the 225. (Yam from memory uses (OK, used on the 2- strokes) the same gearbox on approx 50- 90Hp, so going to be about as small as a 90 gearbox will get), then add the fact the single gets a bit more speed so the drag goes up by the square of 6 knts - Ribcraft's numbers may not be too far out.

As for the servicing, you still need to keep the aux running, so you end up servicing two anyway. As you won't be able to buy a 2- stroke, I bet you end up with something in the 15-25Kg ballpark, so how much lighter is a big single really going to be?


My take on it - if those are tested figures, I'd go twin, But I do my own servicing....

On my previous posts, I have given examples where twins are actually lighter - Never generalise in these kind of discussions!
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