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carparkthrasher

Lunchbox front end!

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Hi all,

As per my showroom updates I built a 58347 Lunch Box this weekend as I felt I needed one in my life after all these years! Build was fun and I even enjoyed the painting. Aside from a slightly hot motor and ESC, the only off plan addition was to build it with the CVA shock upgrades from day one and not retro fit. Built exactly as per instructions so piston, spaces and damper end as manual and soft spring as manual.

All good when standing still and when popping a wheelie, however when the front end comes back to earth - at any speed - the whole thing collapses in and the front wheels bow in so much as to rub on the springs on the shocks, binding the whole thing up. To rectify this I used the strong spring on the front with a pre load spring jobbie and this has stopped the collapse.

Whilst I know the Lunch Box is no high spec club racer with pin point steering but does this sound right that she is that bad? Fair enough she is a fun little car but to not actually be able to drive it at slow speed seems odd! Am pretty sure I did everything right, build wise - is this just a quirk of the Box?

Also, while I have you! The other problem I have is with the front tyres coming off the wheel, specifically front left. Now I have put this down to the fact that after spending ages trying to get the tyres on perfectly, I noticed that the inner rim of the tyres (that fits into the grooves on the wheel) is a different thickness from one side to the other. I could understand this if this was for tyres that were left and other that were right - particular tread pattern etc. However, these are ambidextrous and should be identical. However what I am finding is that the tyres on the left of the car (looking down on it, nearside to relate to a 1:1) fit perfectly on the outer rim of the wheel but not on the inner. The reverse is true for those on the right.

I have a whole second set of tyres and gold wheels that all exhibit the same problem. Is this the norm? Does anyone else see this? Will a dab of glue shut me up?

Thanks all!

CPT

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Since yesterday I'm also experiencing the exact same problem regarding the tyres. I re-fitted the tyre this afternoon - time will tell if the problem persists..

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Check out what I did to my Lunchbox. It actually handles pretty good now. Well as good as a 2WD monster truck can handle anyway. Showroom.

I needed to glue my tyres to the wheels to stop the front tyres demounting when landing from a wheelie. And also to stop them all ballooning off at high speed.

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Check out what I did to my Lunchbox. It actually handles pretty good now. Well as good as a 2WD monster truck can handle anyway. Showroom.

I needed to glue my tyres to the wheels to stop the front tyres demounting when landing from a wheelie. And also to stop them all ballooning off at high speed.

+1, the crp front suspension kit for the futaba fx10 is an awesome upgrade to lunchies/pumpkins/hornets and hoppers.

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I have a set of Lunchbox wheels tyres fitted to my Frog/Mudblaster bitza and I noticed that all the tyres seem to be "handed" and i can't get them to sit the same on both sides unless thay are all fitted the same way on the wheels; i.e. the tread on one side of the car faces backwards and the other forwards, even then I can't seem to get them to fit into the rims. I haven't tried lubricant on the beads yet but the tyres on my Monster beetle and touring car wheels have not got this problem and "pop" into the rims perfectly.

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Sounds a little odd really.. I know for sure my lunchbox doesnt do that, and my pumpkin never did back in the day when it had the standard pogo stick springs..

The problem could have been caused by the springs simply being too soft, the shock oil too soft, the front tyres too soft, maybe a combo of all 3.

I'd also look at how the steering is set up, in case you have too much toe out - if when going in a straight line, the front wheels are toeing out slightly, the front suspension would tend to collapse as its geometry is a little "crude"..

You shouldn't need to resort to the CRP suspension kit (though I did on my pumpkin simply because its cool!) the correct steering alignment and damper/spring settings should fix it :P

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Is the CRP kit readily available? If so, any ideas where?

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Is the CRP kit readily available? If so, any ideas where?

Directly from TeamCRP. The front end kit is for the Futaba FX-10 buggy, and not for Tamiya's. It can be modified to fit as the two front ends are similar.

I've done the conversion three times now. To a Grasshopper, then a Lunchbox, and then to a Hornet. It's pretty straight forward on the Lunchbox. On the Grasshopper and Hornet it requires cutting the chassis quite a bit.

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I have a set of Lunchbox wheels tyres fitted to my Frog/Mudblaster bitza and I noticed that all the tyres seem to be "handed" and i can't get them to sit the same on both sides unless thay are all fitted the same way on the wheels; i.e. the tread on one side of the car faces backwards and the other forwards, even then I can't seem to get them to fit into the rims. I haven't tried lubricant on the beads yet but the tyres on my Monster beetle and touring car wheels have not got this problem and "pop" into the rims perfectly.

I noticed this too. The inside bead and outside bead are slightly different diameters. Glue solves it.

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My vintage LB with the CRP & other usual mods http://www.tamiyaclub.com/forum/index.php?...mp;#entry405846

Even when stock the front suspension wasnt as soft as you describe. Since day one I have glued the tyres to the rims, cornering used to peel them off of the outside of the wheel.

The side walls of the tyre are very soft, I found fitting foam insterts helped.

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Hi all, quick update! A good few weeks ago now (sorry for rubbish updating!) i fitted the 3rd shock mod thanks to some creative dremmeling and guides from this site and I rebuilt the front shock (CVA,oil) to include all the spacers to get rid of the toe in/funny hang from the front. With stiff springs all round and shocks well topped up and re built she goes very well as a recent beach run proved. Have also braced the chassis at front and rear, again folllowing the guides from TC users!

Only the hard stuff do I really see any awkward wobble or diving but even then it is all manageable. All just goes to show that searching on here for tips and answers really does pay off. That and actually using the Dremel in action made it all an enjoyable continuation of the build!

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What piston set up did you go with? All Ive done is change the spring and it got a lot better.

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