Bongo Fury

Hello everyone,

I bought my first Bongo 2 months ago but I have a problem with steering wheel shake at above 60mph. Done the obvious things, front wheels balanced resulted in an improvement, so then had all 4 balanced resulting in even less shake but still there. Swapped back wheels for front wheels and another slight improvement, but still a slight shake. The wheels are 15" alloys, and the inside is a tight fit on the centre protrusion from the hub, so I dont't think that I would need to fit spigot rings. But with these gradual improvements it seems to point to wheels/tyres being the cause?
Thinking of fitting a set of used RX8 Alloys shod in new 235/55/18 Van tyres all round, obviosly giving a larger rolling diameter, but this would only help to improve the speedo accuracy as it is reading way to slow.
I would be hoping that the new wheels and oversize tyres would sort the shake, look the business, improve economy and not worsen the ride quality as much as say 245/45/18 tyres. Lot of money to lay out though if it does not stop the shake. Has anybody tried tyres this big?
Well thats the plan, sailed through the MOT anly a month ago so I can't see that bushes could be causing the shake, unless it was missed on the mot inspection. Any input would be appreciated.

Those tyres are 8.32% larger than standard (see http://www.tyresave.co.uk/tyresize.html) so your speedo may well under-read and therefore be illegal. Wheel wobble does seem to be a very common problems with Bongos, no matter how often you get them balanced
Also 18" tyres can work out expensive

Yes John they maybe too big,(cheaper in that size), I know from the fact sheet" Improving MPG" that 215/70/16 tyres with a diameter of 707.4mm. (46.9mm oversize) results in the speedo reading under by 2 or 3 mph, I hadn't taken in to consideration the legal issues.
As my tyres are worn out I thought i'd go for new wheels as well. Currently running scruffy 15" Alloys on cheap tyres. Was ready to buy a set of RX8 Alloys but after looking deeper in to it on the forum I am now not so sure! Tales of terrible ride, reduced braking performance, and back wheels cracking is the reason for looking for a tyre with a bigger sidewall. Also I'm off to Slovakia in a few weeks and some of the roads there will be bad. So now I don't know what to go for. Need new wheels and tyres in the next couple of weeks.
As for the wobble being such a common problem with non standard wheels it must be the wheels moving on the hubs, spiggot rings and the correct wheel nut tourque? The first time I had the wheels balanced the fitter who was familiar with Bongos made a point about finding out the correct wheel nut torque setting.

I've got 17" wheels with spigot rings, but still get a slight tremble at 65ish. I reckon the only real cure is to get the wheels dynamically balanced on the car - not easy with a 4WD though

Hi
Personally, I think the quality of the tyres, and tread pattern make a helluva difference...having said that, I only buy cheap tyres, due to the roads here, but I had balancing and tracking done in England, and the tracking was the worst offender...plus warped discs...but I also run slightly low pressures in the tyres, to get more even wear, and even with the tracking slightly out, there isn't too much of a wobble...Track rod ends can be another contributor...I'm getting a new rack and track rod ends soon...should drive like new!
Cheers
Helen

Interesting point about the quality of the tyres, and who wants to pay out when budget tyres can be half the price? Then agian there must be a reason why they cost so much less.
Any more info as to how Torchwood ( Improving the MPG on your Bongo ) got on with the toyota 16" wheels with 215/70/16 tyres, any problems apart from the slight speedo inaccuracy , did he ever fit them to the front? Seems increasing the rolling distance could be the logical thing to do.

Mark Norton wrote:Interesting point about the quality of the tyres, and who wants to pay out when budget tyres can be half the price? Then agian there must be a reason why they cost so much less.
Any more info as to how Torchwood ( Improving the MPG on your Bongo ) got on with the toyota 16" wheels with 215/70/16 tyres, any problems apart from the slight speedo inaccuracy , did he ever fit them to the front? Seems increasing the rolling distance could be the logical thing to do.

That was my thinking when I fitted 55s to my 17" wheels (by the way, my speedo is 100% correct with those on according to the satnav). I'm tempted to go up to an even deeper profile next time. It seems to me also that the deeper the profile, the less harsh the ride. From memory, Torchwood fitted oversize wheels to his rear axle only (OK as his was a 2WD, but a no-no on 4WD), giving it a rather neat nose down dragster look.

Just "won" a set of RX8 18" Alloys off Ebay in good condition. Looking at possibly fitting 235/50/18 tyres which are 4.69% oversize over standard, or 225/55/18's which are a 6.6% increase. Believe Torchwoods rears are a 6.96% increase. Can get the load and speed rating in these sizes at a reasonable price, £374 for a set of 4 Falkens, Michelin's at £157 each. http://www.camskill.co.uk.

Mark Norton wrote:Just "won" a set of RX8 18" Alloys off Ebay in good condition. Looking at possibly fitting 235/50/18 tyres which are 4.69% oversize over standard, or 225/55/18's which are a 6.6% increase. Believe Torchwoods rears are a 7.1% increase. Can get the load and speed rating in these sizes at a reasonable price, £374 for a set of 4 Falkens, Michelin's at £157 each. http://www.camskill.co.uk.

Just watch out deep profile don't foul the front bumper on sterring lock to lock. This was pointed out by Russian Bongo owner DemonAV a longtime back. Not a serous problem even though, as you can cut away a small portion of bumper to allow full unrestricted movement. I'd be tempted by the 55s provided you are OK with the 'big wheel look' (I wish I could find some great pics posted by DemonAV a long time back of Russian Bongos with big alloys and deep profile tyres, all in deep snow - I searched but could not find them)

The mistery of wheel shake is becoming clearer.
Drove to Birmingham and back to London yesterday only to have the wheel shake get progressivly worse. What started as a tremble turned in to full on judder. Took off one front wheel to investigate:
I had put the wheel on carefully and tightened the wheel nuts FT. Obviously because of the dammage from the hub protrusion it seems the wheel nuts are not holding the wheel. Looked up the wheel nut tourque is 12-15 Kg.m.
Should I be using spiggot rings I wonder? The wheels sit on the hubs quite nicely but the bolt holes in the wheels do seem big for the studs. This wheel looks the same fit on the hub as the RX8 wheels I have just got, so are spiggot rings usually used wth RX8 wheels? I would think steel wheels being stronger would not suffer this problem.

Spigot rings are not needed with RX8 wheels, as the centre bore is the same (67.1mm). If your centre bore is more than that, you will need spigot rings to bring the hole size down to 67.1.

Finally sorted the wheel shake!
I had changed my old alloys for Genuine Mazda RX8 Alloys with new 235/50/18 Tires, but this made no difference to the problem. I found that the wheels were still moving on the hub as in the pictures of my old alloys. I could re-seat the wheels and the shake would be reduced only to return after a trip down the motorway.
I had had tracking done by ATS and watched the guy do the tracking spot on. This made the drive worse! Out of desparation I took it to a 4 wheel tracking specialist, the kind that you get a computer print out. One wheel was only very slightly out, but this made a huge difference, they pointed out that Bongo's are very sensitive to tracking also they thought the taper on the wheel nuts did not look long enough.
Bought some new non mazda wheel nuts on advice from Rochford Tyres, and this has stopped the wheels moving without over torquing as recommended in the Mazda service bulliten. Now no shake.

Do you have a link, or a description of the new nuts?

Email James at " [email protected] ". He does not advertise these nuts. 12x1.5 Radius Nuts £34.95 a set delivered. Only ordered them from him two weeks ago so he should remember, I had asked him for advice to cure the RX8 alloy wheels moving on the hubs on a Bongo.

Here is a interesting quote from the Mazda service bulletin found on the RX8 owners club. For RX8 alloy wheels to cure a snapping noise from the front suspension when the vehicle is turning at low speed, [slippage of the wheel against the hub].
Mazda service bulletin No: 02-002/04 : The workshop manual specifies a lug nut torque of 88-118N.m [65-87ft-lb], but for a field countermeasure, bu sure to torque the lug nuts to 147N.m [108ft-lbs].