removing the rear bumper

[John M. Skowron]

I have a 2004 Monza 32A with the old style round bar rear bumper, not the same as the Birel I had previous to that. It attaches itself to the chassis the same as other chassis I have owned. But, whenever I try to remove it, it is a nightmare. The bolts get ruined in the process, etc. I must be doing something wrong. Is there a standard method for installing and removing the complete rear bumper assembly?

[Chris Lobaugh]

I'm having trouble with the "ruining the bolts in the process." Do you have the head of the bolt in the frame and the nut on the outside so as to run the rear crash bar loose?

[John M. Skowron]

Yes. The head of the bolt is inside the frame. That is the way I assembled it originally and the way most karts I have owned were assembled. I noticed that the Birel catalog shows the head of the bolt on the outside in the drawings. Not sure how to run the lower crash bar loose in that configuration.

A friend of mine made me a large hex cap that i can put on the end in order to loosen the flange nut without turning the bolt in the process. Works pretty well. I used to have to use vise grips to hold the bolt in place, which ruined the threads. The lower crash bar ruins the threads anyway because it is loose.

Am I doing something wrong?

[Simon Fea]

We've got two nyloc nuts on each side - one to tighten the rubber bung that holds the bumper onto the chassis rail, and one at the end of the thread to hold the lower bar on. I cut a slot in the end of each bolt so that we can hold it with a screwdriver while adjusting the nuts. Our loose lower bar has also made a mess of the threads, so we can't undo the inner nut much now. Hopefully we've got enough turns to be able to remove the bumper if necessary.

We live in New Zealand and I think we've probably got the only Monza in this country. We've had to do some interesting things to get it to perform! We've installed camber/caster adjusters from a different brand (Arrow), for example.

I'd be very interested to compare notes with any other correspondents who have Monzas. I'd be happy to exchange email addresses if it can be arranged. Of course things of general interest should go on the forum.

Thanks
Simon

[John M. Skowron]

I am very happy with my Monza Z32A in 125 cc TaG class. I recently had to play with caster/camber as well due to some sticky track situations, but got it figured out. I have heard of people putting some sort of plastic or rubber sheath over the threads to keap them from wearing. Or you can grind the threads off in that section to prevent nut removal issues.

[Andy Finke]

Try wrapping the lower bar with electrical tape around the bumper bolt. This allows the chassis to move independent of the bar, but stops the bar from vibrating and wearing the threads.

Works great!

Andy

[Chris Lobaugh]

Andy's got the right idea with the electircal tape. Otherwise you have to keep a m10x1.5 die in your toolbox to get the bumper off (or a hacksaw). I had a friend weld an 8mm bolt to the head of the 10mm bumper bolt (head to head).. The bumper is held on with the nut on the inside of the frame and the crash bar is held in place with the 8mm bolt (I use those front driver panel rubbers to rubber mount the crash bar and it looks prettty trick and you never have problem removing the bumper).
regards,
chris

[John M. Skowron]

I like all of those ideas. I may one or two of them. thanks.