888 SP4 Airbox

KevB

Currently running open airbox/filter. Can anyone advise on the airbox lid part and airbox hose connectors part numbers for the SP4? Unable to find any reference or pictures for these parts and the gubbins under the tank so not sure which airbox part is required or will fit or, if indeed, there is actually an airbox lid at all?! Cheers :-)

Mr.R

The SP4 had the same airbox as the '92 851's, finding one that hasn't been cut about might be a tad hard.

Steve R

KevB

Mr.R wroteThe SP4 had the same airbox as the '92 851's, finding one that hasn't been cut about might be a tad hard. Steve R

Hi Steve, thanks for help. So far every reference I have found is for an open air box. Even the parts catalogues don't seem to include an airbox top and connectors, athough the owners manual shows one. A couple of guys have kindly sent photos with the tank off and they all match mine (i.e. the air pipes are just suspended under the tank held in place by a zinc coloured spring/wire). I am slowly replacing perishables and sort of assumed I was missing a part :-) Perhaps not after all...

Cheers again, Kev.

stiglarsenDK

No lid

As far as i know, the sp4 did not have a lid, but a metal frame to hold the filter.

Same for the SPS, that has airtubes directly into the Big rubber boot

griff851

Parts diagram 888 sp 1992.

KevB

Thanks chaps,

That is what I figured from the parts diagram but the whole set up is pretty 'Heath Robinson' with the air tubes just ending under the tank. Absolutely no pressure... Good to have it confirmed though. I have been kindly sent some photos from another SP4 and it mirrors mine so I guess there is nothing amiss. Just looks pretty random and the air tubes can't have much effect other than trickling in a little extra air to the mix...

Thanks for the help. Cheers, Kev.

griff851

There is a lot of stuff going on around “air box” and positive pressure in the 851/888 series development. It covers from the early 88’ race bike, a cavity with air being allowed in from everywhere, then still air boxes, then still air boxes with ram feed. All of which really doesn’t eventuate into a more modern recognisable design until the airbox design of the 748/916.
The SP4/5 probably is about the best of the series. The ram air is ducted to flow up and hit the bottom of the tank forming a positive pressure curtain for want of a better explanation. The trick being to ensure still air around the velocity stack so it’s operating at maximum efficiency. Mean while the japs are attempting nail the concept as well. It’s actually quite amazing what has to happen to obtain efficiency. I’ve seen some air/sound graphics on the cbr250’s airbox and its pretty out there.