Air suspension

Technical questions and answers about the Mazda Bongo

Moderators: Doone, westonwarrior

User avatar
dandywarhol
Supreme Being
Posts: 5446
Joined: Mon Dec 19, 2005 10:18 pm
Location: Edinburgh

Re: Air suspension

Post by dandywarhol » Wed Aug 19, 2009 2:07 pm

My van is unconverted and with a row of seats out. From memory it came in at just under 1800 kg on a weighbridge "unladen"

I don't carry excessive weight in mine - a scooter weighs 110 kg and the nose weight with the trailer "seemed" less than that. As Steve said, it's to stop the rear hitting the bumpstops, maybe there's different springs on yours Ron, mine would bottom out on undulations with only 2 people in the back. The airbags also help with body "sway", especially with a full topbox

PS. I haven't run it past the Police - I don't feel the need too.............. :wink:
Whale oil beef hooked
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
User avatar
Ron Miel
Supreme Being
Posts: 2239
Joined: Tue Oct 21, 2008 5:40 pm
Location: Cheshire

Re: Air suspension

Post by Ron Miel » Wed Aug 19, 2009 6:23 pm

dandywarhol wrote:My van is unconverted and with a row of seats out. From memory it came in at just under 1800 kg on a weighbridge "unladen"

I don't carry excessive weight in mine - a scooter weighs 110 kg and the nose weight with the trailer "seemed" less than that. As Steve said, it's to stop the rear hitting the bumpstops, maybe there's different springs on yours Ron, mine would bottom out on undulations with only 2 people in the back. The airbags also help with body "sway", especially with a full topbox

PS. I haven't run it past the Police - I don't feel the need too.............. :wink:
Apology dandy. I did say "posts....which suggest that some people do buy them in order to carry heavier loads..", whereas I clearly should have said "...may buy them...."

Hope you agree anyway, that it's important not to think they are intended to increase payloads. Some of the (mainly American) websites selling them do seem to suggest that's one good reason for buying them.

If numbers of Bongo owners actually go down that route (and let's face it, many of us would like more payload), we could get to a situation where we're all a bit suspect, and forever getting pulled over.
2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper

(Ron miel=honey rum from the Canaries)
User avatar
missfixit70
Supreme Being
Posts: 12431
Joined: Fri Jun 01, 2007 3:53 pm
Location: weymouth

Re: Air suspension

Post by missfixit70 » Thu Aug 20, 2009 12:06 am

What Dandy said :wink: I wonder if it's to do with the older springs on an older bongo? certainly wouldn't say mine's overloaded when it bottoms out. Mine arrived today from Matt Savage, quick delivery & looks a good bit of kit, just wondering if I could fit a similar system to my knees :roll:
You can't polish a turd - but you can roll it in glitter.
User avatar
Ron Miel
Supreme Being
Posts: 2239
Joined: Tue Oct 21, 2008 5:40 pm
Location: Cheshire

Re: Air suspension

Post by Ron Miel » Thu Aug 20, 2009 12:21 am

missfixit70 wrote:What Dandy said :wink: I wonder if it's to do with the older springs on an older bongo? certainly wouldn't say mine's overloaded when it bottoms out. Mine arrived today from Matt Savage, quick delivery & looks a good bit of kit, just wondering if I could fit a similar system to my knees :roll:
Good point about the knees Kirsty - I'll see if I can get some air lifts on the NHS when I go in for surgery next month :lol: Mind you, I was once promised hand maidens on the NHS by our GP, and they never materialised - budget cut, I suppose.

Re the Bongo springs, it might also be that some of the cold weather spec Bongos have uprated springs, anyway. Mine is spec'd for 195/80/R15 and 215/70/R15 tyres (for chunky winter tyres?), rather than the usual 70 and 65 profiles so there's a bit more ground clearance in which to fit longer travel springs. Would appreciate inputs on how the air lifts affect general ride comfort, if at all, as opposed to handling - good or bad? If good, I might fit some as anything reasonably priced, which makes the normal ride better is probably worth having in my book.
2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper

(Ron miel=honey rum from the Canaries)
bigdaddycain
Supreme Being
Posts: 10637
Joined: Fri May 13, 2005 11:58 am
Location: Ince Lancs

Re: Air suspension

Post by bigdaddycain » Thu Aug 20, 2009 1:10 am

Ron Miel wrote: Mine is spec'd for 195/80/R15 and 215/70/R15 tyres (for chunky winter tyres?), rather than the usual 70 and 65 profiles
That's because yours is a new shape Dave. :wink:
ビッグダディケイン RIP Big Bank Hank (Imp the Dimp) 1957-2014
User avatar
Ron Miel
Supreme Being
Posts: 2239
Joined: Tue Oct 21, 2008 5:40 pm
Location: Cheshire

Re: Air suspension

Post by Ron Miel » Thu Aug 20, 2009 10:10 am

bigdaddycain wrote:
Ron Miel wrote: Mine is spec'd for 195/80/R15 and 215/70/R15 tyres (for chunky winter tyres?), rather than the usual 70 and 65 profiles
That's because yours is a new shape Dave. :wink:
Hi BDC. Are you sure? Think I've only ever seen one ref to 80 and 70 profile standard tyres on here, and didn't pick up that it was new shape specific. Just searched "new shape tyres" and "new shape tyre sizes" and, the only 15" wheel tyre sizes confirmed in immediate search results there were 70 and 65 profiles - but whether the original fit tyres were also in those sizes isn't immediately clear. Will delve more into those threads, and look again for that one 80/70 ref I remember seeing before, later today when I've got more time. I guess it would make sense that springs were tweaked on the new shapes if bottoming out is as common as it seems to be here on earlier Bongos. Regards, David
2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper

(Ron miel=honey rum from the Canaries)
User avatar
dandywarhol
Supreme Being
Posts: 5446
Joined: Mon Dec 19, 2005 10:18 pm
Location: Edinburgh

Re: Air suspension

Post by dandywarhol » Thu Aug 20, 2009 12:02 pm

Trying to avoid repeating myself and boring folks but the airbags have no negatives in my book. My '96 diesel has a soft a spring rate coupled to fairly stiff damping. I measured the springs and they appear to be within spec so they're just soft - it's a common complaint on budget spec Jap motorbikes.

The airbags only really come into operation when there's a demand put on them, i.e. cornering smartly when the high centre of gravity induces excessive body roll, undulatory surfaces when the springs/dampers can't keep up and when there's an extra load in the rear or weight is placed towards the rear. They also keep the van level when there's 2/3 passengers in the back which makes the van steer/track more accurately.

The bongo is a poor handling vehicle as standard IMO - it roadholds well but doesn't handle like a modern Eurovan - it tends to need a bit of steering input when tramping on :?

The airbags (lightly pressurised) don't lift the vehicle - they just don't allow it to sag when loaded. Whats more, the standard dampers are more than up to the job too, which surprised me and was an added bonus. I suppose as there's less spring movement due to softness there's less probability of the dampers overheating.
Whale oil beef hooked
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
User avatar
Ron Miel
Supreme Being
Posts: 2239
Joined: Tue Oct 21, 2008 5:40 pm
Location: Cheshire

Re: Air suspension

Post by Ron Miel » Thu Aug 20, 2009 7:01 pm

Ron Miel wrote:
bigdaddycain wrote:
Ron Miel wrote: Mine is spec'd for 195/80/R15 and 215/70/R15 tyres (for chunky winter tyres?), rather than the usual 70 and 65 profiles
That's because yours is a new shape Dave. :wink:
Hi BDC. Are you sure? Think I've only ever seen one ref to 80 and 70 profile standard tyres on here, and didn't pick up that it was new shape specific. Just searched "new shape tyres" and "new shape tyre sizes" and, the only 15" wheel tyre sizes confirmed in immediate search results there were 70 and 65 profiles - but whether the original fit tyres were also in those sizes isn't immediately clear. Will delve more into those threads, and look again for that one 80/70 ref I remember seeing before, later today when I've got more time. I guess it would make sense that springs were tweaked on the new shapes if bottoming out is as common as it seems to be here on earlier Bongos. Regards, David
Had a bit more of a delve but am not any further forward in understanding why our Bongo, and seemingly just a few others, has 195/80, 215/70 tyres specified. Certainly there are plenty of "new shapes" out there with "normal" (195/70, 215/65 or 215/65 all round) tyres fitted now, and I've only found one reference to some (sic) later Bongos having the higher profile tyres - so I still don't know if it's a rare mutation, or if it did did relate to all new shapes at birth. Perhaps we shall never know - as they keep saying in "Who do you think you are?" (which should be sub-titled "Who cares?", in some cases 8) )
2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper

(Ron miel=honey rum from the Canaries)
User avatar
Ron Miel
Supreme Being
Posts: 2239
Joined: Tue Oct 21, 2008 5:40 pm
Location: Cheshire

Re: Air suspension

Post by Ron Miel » Thu Aug 20, 2009 7:10 pm

dandywarhol wrote:Trying to avoid repeating myself and boring folks but the airbags have no negatives in my book. My '96 diesel has a soft a spring rate coupled to fairly stiff damping. I measured the springs and they appear to be within spec so they're just soft - it's a common complaint on budget spec Jap motorbikes.

The airbags only really come into operation when there's a demand put on them, i.e. cornering smartly when the high centre of gravity induces excessive body roll, undulatory surfaces when the springs/dampers can't keep up and when there's an extra load in the rear or weight is placed towards the rear. They also keep the van level when there's 2/3 passengers in the back which makes the van steer/track more accurately.

The bongo is a poor handling vehicle as standard IMO - it roadholds well but doesn't handle like a modern Eurovan - it tends to need a bit of steering input when tramping on :?

The airbags (lightly pressurised) don't lift the vehicle - they just don't allow it to sag when loaded. Whats more, the standard dampers are more than up to the job too, which surprised me and was an added bonus. I suppose as there's less spring movement due to softness there's less probability of the dampers overheating.
Good info thanks dandy. Your use seems to be more about cornering smartly and tramping on than concerns me, so I conclude that I don't at present need them, and if they don't affect ride comfort, I guess I also don't want them.
2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper

(Ron miel=honey rum from the Canaries)
User avatar
mister munkey
Supreme Being
Posts: 5184
Joined: Mon Oct 01, 2007 9:11 pm
Location: Not Far From Royston Vasey, West Yorkshire
Contact:

Re: Air suspension

Post by mister munkey » Thu Aug 20, 2009 7:21 pm

Can you make it do this though?

http://www.youtube.com/watch?v=P-ZcocgSw2I

:?:
The only true wisdom is in knowing you know nothing. http://www.travelblog.org/Bloggers/MisterMunkey
User avatar
missfixit70
Supreme Being
Posts: 12431
Joined: Fri Jun 01, 2007 3:53 pm
Location: weymouth

Re: Air suspension

Post by missfixit70 » Thu Aug 20, 2009 8:25 pm

Not with the ones I bought, but Francophiles does that :wink: Springs are removed & replaced with a double doughnut type arrangement, compressor in the back & valves in the cab :wink:
You can't polish a turd - but you can roll it in glitter.
User avatar
dandywarhol
Supreme Being
Posts: 5446
Joined: Mon Dec 19, 2005 10:18 pm
Location: Edinburgh

Re: Air suspension

Post by dandywarhol » Fri Aug 21, 2009 12:28 am

Hi BDC. Are you sure? Think I've only ever seen one ref to 80 and 70 profile standard tyres on here, and didn't pick up that it was new shape specific. Just searched "new shape tyres" and "new shape tyre sizes" and, the only 15" wheel tyre sizes confirmed in immediate search results there were 70 and 65 profiles - but whether the original fit tyres were also in those sizes isn't immediately clear. Will delve more into those threads, and look again for that one 80/70 ref I remember seeing before, later today when I've got more time. I guess it would make sense that springs were tweaked on the new shapes if bottoming out is as common as it seems to be here on earlier Bongos. Regards, David
Had a bit more of a delve but am not any further forward in understanding why our Bongo, and seemingly just a few others, has 195/80, 215/70 tyres specified. Certainly there are plenty of "new shapes" out there with "normal" (195/70, 215/65 or 215/65 all round) tyres fitted now, and I've only found one reference to some (sic) later Bongos having the higher profile tyres - so I still don't know if it's a rare mutation, or if it did did relate to all new shapes at birth. Perhaps we shall never know - as they keep saying in "Who do you think you are?" (which should be sub-titled "Who cares?", in some cases 8) )
I was under the impression that the winter M+S tyres were a higher profile on the bongo - I think I read that in the owner's handbook.

PS - I don't "tramp on" all the time Ron - it's just not that kind of vehicle - but there's been occasions when the traffic is moving smartly on quick A class or N class French roads and I don't like to hold folks up behind me. :wink:
Whale oil beef hooked
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
User avatar
Ron Miel
Supreme Being
Posts: 2239
Joined: Tue Oct 21, 2008 5:40 pm
Location: Cheshire

Re: Air suspension

Post by Ron Miel » Fri Aug 21, 2009 8:14 am

dandywarhol wrote:
Had a bit more of a delve but am not any further forward in understanding why our Bongo, and seemingly just a few others, has 195/80, 215/70 tyres specified. Certainly there are plenty of "new shapes" out there with "normal" (195/70, 215/65 or 215/65 all round) tyres fitted now, and I've only found one reference to some (sic) later Bongos having the higher profile tyres - so I still don't know if it's a rare mutation, or if it did did relate to all new shapes at birth. Perhaps we shall never know - as they keep saying in "Who do you think you are?" (which should be sub-titled "Who cares?", in some cases 8) )
I was under the impression that the winter M+S tyres were a higher profile on the bongo - I think I read that in the owner's handbook.

PS - I don't "tramp on" all the time Ron - it's just not that kind of vehicle - but there's been occasions when the traffic is moving smartly on quick A class or N class French roads and I don't like to hold folks up behind me. :wink:
"M+S"?

You're right dandy. There are several Bongo variants/grades specified with 195SR 15, 215/70 15 tyres, in the handbook but I don't know what the "grades" in question (e.g., "RF-V") mean. Do you? Are they all winter spec Bongos? Strangely, they're also the ones specified with lower ground clearance, 155 mm instead of 175 mm, so I took that to mean body skirts - which ours does not have.

Anyway, according to the Amayama index of models/grades/years, they do not mean new type. Presumably a 195SR 15 front tyre has an 80% profile, although ours is actually plated 195/80 15, to go with its 215/70 15s on the back. No mention of 195/80 15 in the handbook, as far as I can see.

Re "tramping on", that was just a gentle leg pull, and I also used to ride bikes (EDIT: Oh, the bit about bikes was in another thread!) - with exhilaration as one of the benefits, except in 'orrible cold weather. It's true though, that having survived our roads, driving from age 17 to now 71, I don't require quite as much cornering grip as younger drivers might need - but often haven't got :( Good braking performance, to compensate for perhaps taking 5 or 10 minutes to decide to push that pedal, is paramount :lol: No, that''s a wind up too. My reactions are, thank god, still pretty quick.
2001-V6-LPG-AFT-black on silver-Imperial Purbeck camper

(Ron miel=honey rum from the Canaries)
volamoose
Bongonaut
Posts: 40
Joined: Tue Aug 02, 2005 4:04 pm
Location: Pembrokeshire

Re: Air suspension

Post by volamoose » Fri Aug 21, 2009 12:29 pm

hiya, I've had my bongo lowered using the lowering springs from bell hill. would these airbags still fit? or do they onlly fir in a standard coil spring, my van has never bottomed out before but with all the camping gear in the back or a couple of adults sat in the back it has strted to if i go over a bump or dip.
Bingo, Bango.........
User avatar
missfixit70
Supreme Being
Posts: 12431
Joined: Fri Jun 01, 2007 3:53 pm
Location: weymouth

Re: Air suspension

Post by missfixit70 » Fri Aug 21, 2009 1:14 pm

volamoose wrote:hiya, I've had my bongo lowered using the lowering springs from bell hill. would these airbags still fit? or do they onlly fir in a standard coil spring, my van has never bottomed out before but with all the camping gear in the back or a couple of adults sat in the back it has strted to if i go over a bump or dip.
I guess you'd have to take some measurements & speak to the supplier, they come in different sizes, so you may have to go for a slightly smaller one?
You can't polish a turd - but you can roll it in glitter.
Post Reply

Return to “Techie Stuff”