I don't like my Al-Ko chassis

[candapack]

Joe90 - 2015-06-12 3:44 PM

 

However, must go the missus is getting techy, on the forums and supposed to be on holiday.

 

Women getting techy, whatever next. I thought they just fell in love with the blokes that did the techy stuff for them, and cried a bit.

Oh dear, s'pose I'm going to have to resign from something now.

:D

[Steve928]

Brian Kirby - 2015-06-12 4:35 PM

 

[i'm guessing, but I wonder if that may be a clue. If the chassis is dropped, and if the van floor sits fairly close to the trailing arms (as seems the case from your photo), it would seem necessary to restrict suspension travel to prevent either the chassis grounding, or the arms striking the van floor on full bump. I just wonder if they are using a stiffer torsion bar to achieve that, and it is that which is resulting in the harsher ride. Law of unintended consequences? Might be worth asking if they can comment.

 

That's a very good point. Although the swingarm itself could not hit the floor or wheelarch, clearly the hose and wiring would should there be more (read any) travel available. Law of unintended (although possibly well understood but not mentioned in promotional literature) consequences.

[urbanracer]

I had made my mind up to order a new Bailey motorhome with 'a new ultra low profile lightweight chassis

AL-KO AMC' in fact I should have already ordered it.

 

People I asked said it was far better than the standard chassis and gave a smooth ride with better handling.

 

What do I do now?

[Tracker]

urbanracer - 2015-06-12 7:07 PM

 

I had made my mind up to order a new Bailey motorhome with 'a new ultra low profile lightweight chassis

AL-KO AMC' in fact I should have already ordered it.

 

People I asked said it was far better than the standard chassis and gave a smooth ride with better handling.

 

What do I do now?

 

Didn't you drive one before you ordered it?

 

If not best go and drive one now and hope that it is comfortable if for no other reason than you will at least have a base line comparison point if yours is harsher than expected.

 

That said these are basically commercial load carrying vans and will never have the ride quality of a decent car so don't expect miracles!

[urbanracer]

No I have not ordered yet and I would need a test drive but the van is the layout design etc I liked.

It was people who had this type of AL KO chassis who said it was good also people who serviced the motorhome trade( not dealers) and even someone who raced cars who said how good the performance is.

I have had 3 X250's and I like how they drive but the Al KO has had better reports.

[Tracker]

urbanracer - 2015-06-12 7:32 PM

 

No I have not ordered yet and I would need a test drive but the van is the layout design etc I liked.

It was people who had this type of AL KO chassis who said it was good also people who serviced the motorhome trade( not dealers) and even someone who raced cars who said how good the performance is.

I have had 3 X250's and I like how they drive but the Al KO has had better reports.

 

That's a relief!

I know some people buy without test driving but I will never understand why they take such a gamble?

Perhaps be as well to drive a couple of Alko chassied vans to get a better feel for the set up?

I never heard anyone grumble about Alko on the older chassis (apart from ground clearance and turning circle) and I must admit to some surprise that the newer ones maybe not so good but with more than just one person complaining maybe there is an issue with them that warrants investigation before buying?

[Rayjsj]

Tracker - 2015-06-12 2:32 PM

 

We had an Alko chassis on our Autocruise Starlet but that was on the previous model Sevel X244 and may not compare with a new one for set up?

 

We found it by far the most stable, smooth, and comfortable riding van we have ever had and I only wish we had one now - but not from what you are saying?

 

I no longer have the handbook as it went with the van but the Alko suggested tyre pressures were around 50 psi as I recall, whereas Peugeot suggested much higher pressures.

 

Overly hard tyres all round when we collected the van totally negated the intrinsically softer suspension of the Alko units and it was only when I let them down to what Alko said, along with the fronts which Alko also gave as lower than Peugeot suggested, that the ride improved to what it should be.

 

As the lwb Alko made for a very long wheelbase the downsides were a massive turning circle and low ground clearance around the midpoint of the wheelbase, but as the rear overhang of the van was only about 3' the weight on the rear axle was less than with a longer overhang which made for much better better ride and handing.

 

Tyre pressures may well be the solution?

 

I concur with Tracker, having owned the same model for 4 years, only drawback with the short overhang and ultra low Alko chassis was the very large turning circle, which was a bit embarrassing at times. But the ride and handling was superb, 'cornered like a train' . I would get the axle Greased (properly with the weight removed). and checked. Ray

 

didn't realise Alko had changed the design....why ?

[lennyhb]

Something just doesn't sound right, our current van has the Al-Ko AMC chassis, which we find much softer sprung than the previous Hymer on the Fiat X250 Camping Car chassis. The Al-Ko chassis rides smoother, quieter & none of the crashing over bumps like the Fiat chassis.

One thing that is noticeable with the Al-Ko is the softer springing gives much more movement inside the van when camped, slightest movement by one of us can be felt right through the van.

Can't say that I've noticed any difference changing tyre pressures, I've tried dropping them to 50 psi from 64 psi, if anything the ride feels better at 64.

Chassis's I assume are tweaked to individual manufacturers requirements, have you spoken to other Bailey owners to see i they have the same problem?

[urbanracer]

I did have a 12 mile test a couple of months ago, it was a Bailey and it was the worst van for

noise from the habitation area I had ever driven.

I have still not made up my mind what will be my next van.

[yoko8pups]

markh1 - 2015-06-12 12:40 PM

 

I had the same until I reduced my rear tyre pressures form the ALKO recommendation of 80 psi to the tyre manufacturers recommendation of 65 psi, ride transformed!

Could you tell me what that is equivalent to in whatever it is i measure my tyres in? Front and back i set them at 5500.

 

[yoko8pups]

markh1 - 2015-06-12 12:40 PM

 

I had the same until I reduced my rear tyre pressures form the ALKO recommendation of 80 psi to the tyre manufacturers recommendation of 65 psi, ride transformed!

Could you tell me what that is equivalent to in whatever it is i measure my tyres in? Front and back i set them at 5500.

 

[yoko8pups]

markh1 - 2015-06-12 12:40 PM

 

I had the same until I reduced my rear tyre pressures form the ALKO recommendation of 80 psi to the tyre manufacturers recommendation of 65 psi, ride transformed!

Could you tell me what that is equivalent to in whatever it is i measure my tyres in? Front and back i set them at 5500.

 

[tonyishuk]

If your m/home started life like this, there is a far chance its got the wrong Alko chassis at rear :D

 

Rgds

[Guest pelmetman]

tonyishuk - 2015-10-07 7:06 PM

 

If your m/home started life like this, there is a far chance its got the wrong Alko chassis at rear :D

 

Rgds

 

So Fiat has finally sorted their reversing issue :D ...........

 

 

[Keithl]

OR...

 

It's for when one breaks down!

[Derek Uzzell]

yoko8pups - 2015-10-07 4:11 PM

 

Could you tell me what that is equivalent to in whatever it is i measure my tyres in? Front and back i set them at 5500.

 

Tyre inflation pressures are normally specified using metric or imperial units and the two scales most commonly used are (respectively) bars or pounds-per-square-inch (psi).

 

There are several on-line websites that allow easy conversion between the scales. Using this example

 

http://www.convertunits.com/from/bar/to/psi

 

it will be seen that 80 psi converts to 5.5158058240082966 bar and 65 psi converts to 4.481592232006741 bar.

 

Realistically, it will not be practicable to set or measure motorhome tyre pressures with very high accuracy, so 80 psi and 65 psi would probably be considered by motorhome owners to be equivalent to 5.5 bar and 4.5 bar respectively.

 

There is another measurement unit (the kilopascal) that might be used and this on-line converter

 

http://www.tvr-webmart.co.uk/tvr_info_psi.asp

 

allows conversion of a KPa figure to the equivalents in bars and psi.

 

I’d expect the tyre pressures advised by Hymer for your motorhome to be specified in bars and I’d guess that the original recommendations might well have been 5.0 bar (front tyres) and 5.5 bar (rear tyres) if the vehicle has 15”diameter wheels, or 5.5 bar (front and rear tyres) if the wheels are 16” diameter.

 

I’d also guess that the “5500” figure you’ve quoted is some sort of misreading of 5.5 bar or 550 KPa.

 

 

[Steve928]

urbanracer - 2015-10-07 3:19 PM

 

I did have a 12 mile test a couple of months ago, it was a Bailey and it was the worst van for

noise from the habitation area I had ever driven.

I have still not made up my mind what will be my next van.

 

I didn't really notice when I test drove mine, too busy concentrating on other things I guess, but I recall being driven home by the delivery driver post-purchase and being genuinely shocked at the rattling and crashing going on behind. I thought it was going to fall apart thumping over the Tay bridge's expansion joints and was beginning to think I'd made a bad mistake. Happily though I've managed to get it quiet, as quiet as any other van I've owned in fact. It takes a little perseverance and several meters of self-adhesive foam strip etc. but it's quite possible. The only thing that just has had to go is the microwave but then microwave rattles can't be Bailey-specific.

[yoko8pups]

Thank you Derek, you have helped me.

[yoko8pups]

Thank you Derek, you have helped me.

[bikey]

Just my own opinion but having had a Arto for 6 years and a hymer for 3 years both new and on a alko chassis both awful hard rides with varying tyre pressure my new ducato pvc on std fiatx290 running gear is much smoother ride.

Would not want a alko chassis again. Just my opinion.

[Steve928]

bikey - 2015-10-08 3:46 PM

 

Just my own opinion but having had a Arto for 6 years and a hymer for 3 years both new and on a alko chassis both awful hard rides with varying tyre pressure my new ducato pvc on std fiatx290 running gear is much smoother ride.

Would not want a alko chassis again. Just my opinion.

 

That's where I'm at too, bikey. The handling is superb, you can keep up with the cars on twisty B roads, but the cost in terms of hard ride are too high. Sevel chassis + air instead of the 'bump stops' for me next time.

[Colin Leake]

Steve928 - 2015-10-08 3:58 PM

 

bikey - 2015-10-08 3:46 PM

 

Just my own opinion but having had a Arto for 6 years and a hymer for 3 years both new and on a alko chassis both awful hard rides with varying tyre pressure my new ducato pvc on std fiatx290 running gear is much smoother ride.

Would not want a alko chassis again. Just my opinion.

 

That's where I'm at too, bikey. The handling is superb, you can keep up with the cars on twisty B roads, but the cost in terms of hard ride are too high. Sevel chassis + air instead of the 'bump stops' for me next time.

 

That's what we've got on our PVC. Double leaf rear springs and and air assist (standard on AutoSleepers) thought the ride may be hard but ride and handeling are superb. Does give a high rear end stance wich means we sometimes need to use ramps on the front to things all nice and level.

[Derek Uzzell]

With a ‘standard’ Ducato motorhome chassis (ladder-frame or panel-van type) the chassis sits above the rear axle and is attached to it by leaf springs. It’s possible – with a specialised ‘camping-car’ ladder-frame chassis - to decrease the chassis depth (to lower the height from the ground of the interior floor) and to increase the vehicle’s rear track (to improve the vehicle’s handling), but the ground clearance beneath the motorhome’s chassis will always be significant and a genuine ‘double floor’ design will not be a practicable proposition.

 

The Al-Ko motorhome chassis has independent rear suspension and the axle-tube passes through the chassis rather than being beneath it. The rear track is wider than standard and – because the of the relocated rear axle position – the top of an Al-Ko chassis is much closer to the ground and a double-floor becomes practicable. If a really low version of the Al-Ko chassis is chosen by the motorhome manufacturer, the ground clearance beneath that chassis will be much reduced and the rear axle’s spring-rate will need to be high to compensate.

 

With a widened track, independent rear suspension and a lowered centre of gravity it should be anticipated that the handling of an Al-Ko chassis-equipped motorhome will be good. Conversely, with restricted vertical rear-wheel travel (unavoidable when the ground clearance is small) and firm damping to keep the rear wheels in check, it should be expected that the ride quality may suffer.

 

The skill will be in matching the Al-Ko chassis type, rear-axle spring-rate and damper settings to the design of the motorhome, so that the potential benefits of the chassis are fully realised and the potential drawbacks are avoided. That Hymer (vastly experienced in building motorhomes) apparently manages to do this well and Bailey (a relative newcomer) apparently does not doesn’t greatly surprise me.

[Steve928]

Derek Uzzell - 2015-10-09 8:54 AM

That Hymer (vastly experienced in building motorhomes) apparently manages to do this well and Bailey (a relative newcomer) apparently does not doesn’t greatly surprise me.

 

With respect, 'bikey' above reports the same hard ride from his Arto and Hymer vans, while Joe90 further up the thread seems to be facing the exact same situation with his Rapido, so the problem would not seem to be limited to one relative newcomer to motorhome manufacturing.

[brom]

We've tested quite a few motorhomes with Al-Ko chassis, as well as many others with the wider Camping Car chassis, and also the standard chassis. When tested, these vans have been relatively lightly laden, sometimes nearly empty. Some have had additional suspension modifications like air-ride, so we couldn't state a hard and fast rule and the following are just general observations:

 

We tend to find that motorhomes with the Al-Ko handle extremely well - and are also low, so easing entry via the habitation door. Some have a harsh and hard rear suspension, which makes interior fittings crash and rattle, and if so, we mention that in the test report.

 

The Camping Car chassis we often find has a more supple suspension, yet also handles well; it sits reasonably low with regard to access, so makes a good all-round compromise.

 

The standard chassis is also supple, but stands higher, so is more likely to lean on corners, making some motorhomes ( but not all - it does depend upon other design features) feel a little top-heavy. Being higher, the habitation door tends to need an external step or steps, particularly if the door is to the rear of the van.