spunky
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 posted on 13/4/04 at 11:59 PM |
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BEC engine mounts
Hi everyone,
How have you BEC builders mounted your engines? Are they all mounted in solid bushes or have any of you tried rubber mounts.
My engine is mounted solid to an IRS back end and after some testing today I'm still finding the clutch very 'grabby' I figured this
may be with the solid mounting there is nothing to reduce the tortional effect of the gear shift (even bikes have a cush drive in the rear wheel).
Or is this just the nature of BEC's
Any comments/advice appreciated.
John
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Hellfire
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| posted on 14/4/04 at 12:07 AM |
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Bushes
On our 'blade engine, it's mounted solid. We have a 'cush drive' as we have two rear wheels! 
Apparently the snatch thing is common to BEC's as there is more feel with the hand than there is with your foot. Try it on your wife/partner...
see which he/she prefers  Sorry, shouldn't put 'snatch' and 'hands' and 'feet' in the same sentaence
should I. Will prompt the 'other side' into comments!
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ChrisGamlin
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| posted on 14/4/04 at 09:31 AM |
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Mine has the ST engine cradle with poly bushes in it, but it doesnt allow it to move very much at all, and lots of people have mounted them solidly
without any problems (they are mounted solidly in the bike frame after all).
What engine do you have? The engine mounts on the top of the gearbox on a blade have rubber bushes in them anyway (hence not a good idea to have two
seperate bolts, one from each end going into these as Ive seen with some builds) so that probably helps dampen a bit, but I wouldnt think any mounts
would affect the clutch feel significantly, thats more likely to be the leverage ratio of the pedal or knackered clutch plates.
Chris
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spunky
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| posted on 14/4/04 at 11:58 AM |
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Mounts
Cheers Chris
Its a Honda SP1, mounted in poly bushes, as you say they make it pretty much rigid.
Engine is 4 years old but Ian at ST had it about 3 years ago fitted in the chassis, so really only 1 year old hence me not checking/fitting new clutch
when I had it on the bench (prat).
Of course being a SP1 it may of spent its short life on the track...fried plates maybe!
I'll run it a bit before removing body, seats, firewall to access clutch.
Thanks for the input
John
Hellfire- the amount of time I'm spending either in an engine bay or hunched in font of the PC late at night, my missus would be thankful for a
grabby crutch, sorry clutch!
[Edited on 14/4/04 by spunky]
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Jasper
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| posted on 14/4/04 at 08:05 PM |
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Solid mounts, smooth clutch here
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Hellfire
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| posted on 14/4/04 at 08:36 PM |
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quote:
Originally posted by Spunky
Hellfire- the amount of time I'm spending either in an engine bay or hunched in font of the PC late at night, my missus would be thankful for a
grabby crutch, sorry clutch!
Being as I'm the one doing the website too - I think we're leading parallel lives! <S>
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spunky
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 posted on 16/4/04 at 07:14 PM |
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Doh!
Got to the bottom of my clutch problems today.
The motor has a sodding slipper clutch fitted!
Oh how lovely that will be to drive on the road...
Anyone want to buy a drag car?
John
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locoboy
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| posted on 17/4/04 at 05:01 PM |
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whats a slipper clutch?
ATB
Locoboy
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ChrisGamlin
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| posted on 17/4/04 at 08:19 PM |
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On the bike it allows the clutch to slip when you are braking and not on the power, to stop the rear wheel locking up from engine braking.
Do the SP1s have them as standard then spunky, you might be able to get a kit to lock it up if they are?
Chris
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spunky
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 posted on 18/4/04 at 08:59 AM |
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Flippin slipper
I dunno Chris, I never considered it while was messing about with different master cylinders and stuff. The TL1000 have them as standard and the SP1
was a homolagation model for World Superbike series so very likely. Poor research on my part.
The slip under engine breaking isn't to much of a probem, since the wheels on a car are much less likely to lock than a bike it will surely help
protect the drive train and prevent over revving the motor IMO. The lack of slip when trying to get a half ton car of the mark however causes me more
problems, much stalling and 'kangarooing' or just manic tyre shredding!
I'll do some R&D today, the Firestorm clutch may fit straight in.
An LSD will help, I have a sierra standard diff. How difficult to swap to Sierra LSD? mounting points, physical size etc. Any of you guys help me on
this.
Cheers
John
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ChrisGamlin
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| posted on 18/4/04 at 12:45 PM |
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Hi John
Im not sure how an LSD is going to help you pull away better, as all it will do is mean both wheels light up when dumping the clutch rather than one!
An LSD only comes in useful booting it out of slow corners stopping the inside wheel spinning away power, still a good upgrade though.
A Sierra LSD is a straight swap as long as you get the same casing size (some come with a 7.5" mounting, some with 7" like most open
sierra diffs). If you can't get the same casing size or cant get the ratio you want then its wouldnt cost too much to get the LSD internals
built into your existing diff anyway, my uncle has just done one for a mate of mine for about £75 I think.
Chris
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spunky
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| posted on 18/4/04 at 01:01 PM |
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Thank Chris.
Doesn't sound too complicated then, reckon I'll live with it for a while then look at upgrading next winter.
Cheers
John
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jimgiblett
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| posted on 21/4/04 at 09:18 AM |
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You can do a straight swap from open to LSD diff so long as (as Chris said the diff size is the standard 7 inch) AND the output shafts
are the same. Rear drum braked cars used push in drive shafts whilst rear disk braked cars (including XR4x4 LSD models) used bolt on
"Lobro" drive shafts.
The Ford viscous LSD is attached internally to the lobro joint and thus AFAIK cannot be fitted with "Pushin" type driveshafts.
IIRC you can get a Quaife ATB for the "Pushin" but this is muchos dollars. And although reputed to be very good it'll probably be
cheaper option to replace the whole rear end with 4x4 drivetrain.
HTH
Cheers
Jim
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spunky
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| posted on 21/4/04 at 10:18 AM |
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Cheers Jim,
It's standard 7" with bolt on drive shafts so should be able to find a replacement LSD.
Shifted the throttle peddle pivot yesterday, now have three times more peddle movement and hopefully a lot more throttle control.
Will take it for a shakedown today to test....
John
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