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Honda blackbird oil pressure dropping
strikerbird - 21/4/14 at 09:17 PM

I did a hillclimb yesterday at loton park in my Honda blackbird engined striker. Just watched a couple of videos from the gopro and I can see on the sharp right hand bends it drops oil pressure
It's already got an acusump that I recharged and checked the day before. The acusump is fitted correctly as I've asked others using the same combination before.
The oil pressure gauge reads anything from 60-80 most of the time but drops to 20-25 on the right handers.
Do you think this is to low? The sumps baffled also. Am I worrying? It's not rattling yet! I can't understand why the acusump isn't keeping the pressure up its only a couple of seconds.

prawnabie - 21/4/14 at 09:23 PM

Has it already discharged before you get to the corner?

strikerbird - 22/4/14 at 09:39 AM

quote:
Originally posted by prawnabie
Has it already discharged before you get to the corner?

No it's up to pressure before the corner so the acusump should be fully charged.
The original bike oil pressure light doesn't come on so without the gauge I'd never know.

tilly819 - 22/4/14 at 10:35 AM

Have you removed the 2 counter shafts? If not remove them and block of the oil feeds to them. I had a very similar problem which resulted in a nice big hole in the side of the crank case.

Here is a a useful link.

http://projectblackbird.co.uk/2011/12/06/balancer-shafts/

The big give away tell when mine went was it suddenly felt like it was down on power before it went bang.

hope this is of some help

Tilly

twybrow - 22/4/14 at 12:39 PM

May Accusump seems to behave in the same way. When I start up and pre-oil, the oil light goes out, but I get no noticeable rise on the oil pressure gauge. Is my pre-charge wrong, is this normal, or is there a problem with my setup? My oil light will still come on very briefly if I really stamp on the brakes (as it comes to a standstill).

strikerbird - 22/4/14 at 02:13 PM

quote:
Originally posted by twybrow
May Accusump seems to behave in the same way. When I start up and pre-oil, the oil light goes out, but I get no noticeable rise on the oil pressure gauge. Is my pre-charge wrong, is this normal, or is there a problem with my setup? My oil light will still come on very briefly if I really stamp on the brakes (as it comes to a standstill).

I've just taken the pipe off the engine and turned the electric valve on to find there is very little flow through the valve. Is yours electric?
I'm going to fit a manual valve and find a dry roundabout.

Nick DV - 23/4/14 at 12:40 AM

quote:
Originally posted by twybrow
May Accusump seems to behave in the same way. When I start up and pre-oil, the oil light goes out, but I get no noticeable rise on the oil pressure gauge. Is my pre-charge wrong, is this normal, or is there a problem with my setup? My oil light will still come on very briefly if I really stamp on the brakes (as it comes to a standstill).


When I switch A/sump on to pre oil for start up, my pressure guage rises quite quickly

hobbsy - 23/4/14 at 01:02 AM

Long time ago but I seem to recall the electric valve is a restriction so the manual one is the one to go for

Jon Ison - 23/4/14 at 10:51 AM

That will be the old electric valve known to be slow the newer ones cant remember the name they gave them are fine.

What pre charge pressure you using ? Worth also checking the pressure gauge on the accusump, its the only thing that's ever gone wrong with mine, it leaked and allowed the pre charge to be lost thus making the sump just a piece of pipe which did nothing, worth checking, the symptoms are as you describe above, pretty much just normal oil pressure behaviour on the gauge as if the accusump wasn't there, make sense ?

[Edited on 23/4/14 by Jon Ison]