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Bumpstop Confusion?

6/15/2018

Almost everyone knows the importance of the bumpstops in our BMW and MINI suspensions. It is not just a failsafe to protect your struts and shocks, but an integral part of your suspension. Your bumpstops are engaged whenever you hit a bump, turn sharply, or even hit a dip in the road. That is why it is important to make sure your bumpstops are in good condition. Not like this:

The above shows why it is almost never a good idea to reuse your old bumpstops when refreshing or upgrading your suspension. We recommend they be replaced at 50K mile mark, perhaps sooner if you drive in snow, salt, or other harsh conditions. Why would you pay to have springs and shocks installed, and then pay again to have bumpstops replaced? Do it right, do it once!

Lots of chatter about which bumpstops to use when you lower your car with lowering springs. Hopefully nobody is still replacing their bumpstops with the same ones or not using any at all. Like reusing old ones, these are both wrong. The key is to get a bumpstop that is shorter than your stock ones to better match the amount of lowering from your spring, so you are not "riding on your bumpstops". This is what BMW itself does, if you compare the non-sport and sport bumpstops for the same car:

That is why we custom match the new bumpstops to every suspension kit we sell. Like these:

But even these are not to be used on every BMW model. Heavier cars need different bumpstops than light cars. Wagons and convertibles need different ones than sedans and coupes. We even have to consider the diameter of the strut shaft and the size of the bumpstop hole!

This is one of the many benefits of getting a Strutmonkey assembled suspension kit... you leave the bumpstops to us!

The "bloody" truth about compressing coil springs.

1/19/2018

Everyone has heard about the dangers of compressing coil springs yourself when trying to do a suspension refresh or upgrade. Fact is that injuries occur and the risk is real. This is true for even professionals as seen in a bunch of Youtube videos, like this one:

And it recently happened to me! I have done hundreds of assemblies on BMW and MINI. I have all the best equipment, including a commerical-grade spring compressor and accessories. I am always careful, but the truth of the matter is that all springs are slightly different and one piece of machinery cannot work perfectly with all of them. Well, a while back I was building a kit and a spring perch under extreme pressure gave way right when I was grabbing the strut. The perch "bit" off the parts of my thumb and palm that were touching it. The above is the result! Extremely painful when it occurred... and again when doctor cleaned it out... and again when the dressing stuck to the wound and had to be pulled off.

LESSON: For all of you thinking of installing a new suspension, the risk is even greater because you may be doing it for the first time and using a $20 auto store rental. Seriously, this why Strutmonkey only sells fully-assembled kits. We do the hard, and sometimes painful, work so you can do what you want: Open the box and install your suspension. And we pretty much do it for free because if you tried to buy all the assorted parts you need, you will likely spend the same amount as our kits, which we build at wholesale prices. Even if you end up bringing your kit to a shop, the labor charge should be up to $300 less than if you walked in with loose shocks and springs. Either way, you win!

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Bumpstop Confusion?

The "bloody" truth about compressing coil springs.

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