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TheJet-09
03-18-2017, 05:38 PM
I'm often a little behind the curve, and know some of you are familiar with Asphalt cars as well, so has anyone seen a Bump Stop Stick before (or had any experience with one)?

https://lefthanderchassis.com/v2a/14_viewproduct_product.asp?idproduct=001LH2000

You need a lower control arm capable of mounting two shocks (in this case a shock and the bump stop stick). For their chassis, Lefthander makes a specific one:

https://lefthanderchassis.com/v2a/14_viewproduct_group.asp?idgroup=2514256

But on my Gen-X, there are two lower shock mounts already (to change motion ratio from what I can tell, so not necessarily the same). And you would need an extra clearance upper, but I'm thinking it could at least be possible?

I don't know that it'd be legal (and that's a whole other discussion anyway), but if nothing else I think it could be a valuable testing tool, and certainly save time when doing so.

Any thoughts?

billetbirdcage
03-18-2017, 06:35 PM
I'm often a little behind the curve, and know some of you are familiar with Asphalt cars as well, so has anyone seen a Bump Stop Stick before (or had any experience with one)?

https://lefthanderchassis.com/v2a/14_viewproduct_product.asp?idproduct=001LH2000

You need a lower control arm capable of mounting two shocks (in this case a shock and the bump stop stick). For their chassis, Lefthander makes a specific one:

https://lefthanderchassis.com/v2a/14_viewproduct_group.asp?idgroup=2514256

But on my Gen-X, there are two lower shock mounts already (to change motion ratio from what I can tell, so not necessarily the same). And you would need an extra clearance upper, but I'm thinking it could at least be possible?

I don't know that it'd be legal (and that's a whole other discussion anyway), but if nothing else I think it could be a valuable testing tool, and certainly save time when doing so.

Any thoughts?

Why do you need something besides a normal travel indicator? We just build our own out of some 1/4" steel rod, just don't see the need for the expense or possible problems with it binding or whatever and the legality of that.

We make/use something more like this https://lefthanderchassis.com/v2a/14_viewproduct_product.asp?idproduct=001LH10007

TheJet-09
03-19-2017, 12:17 AM
I was looking at it for the bump stop aspect, specifically being able to tune it without adding/removing shims. The little I played with bump stops last year, I had no real idea where to start. So for those who use bump stops, once you get a setting you like, do you leave it there through all track conditions, or are adjustments made as the track changes (if you're willing to share)?

Thanks!

King1
03-19-2017, 08:23 AM
I ran bumps and stack springs for a few years, I still haven't figured out if dirt people look at it as an aero thing or a handling thing. With me I saw it as handling but once you get a bump you like and get the compression set correctly and the making contact with the bump doesn't make the car shove the nose then really to me it was a loose/ tight adjustment. Rather than cranking left rear in our out I just played with the location of the lockout nut or the height of the bump stop. I have never mastered t1he art of taking out shims in the slick to get the nose down, you just lose over all grip. Anybody want to weigh in on that??

Basecircle
03-19-2017, 01:50 PM
Curious as well about the tuning aspect of bumps. Looking at the effects of changing bump shims vs spring changes to get the nose as low as possible without digging in the track and how each affects handling/what other adjustments you can make to counter those changes and keep the handling predictable.

MasterSbilt_Racer
03-19-2017, 05:52 PM
I ran bumps and stack springs for a few years, I still haven't figured out if dirt people look at it as an aero thing or a handling thing. With me I saw it as handling but once you get a bump you like and get the compression set correctly and the making contact with the bump doesn't make the car shove the nose then really to me it was a loose/ tight adjustment. Rather than cranking left rear in our out I just played with the location of the lockout nut or the height of the bump stop. I have never mastered t1he art of taking out shims in the slick to get the nose down, you just lose over all grip. Anybody want to weigh in on that??

Your bump determines that ultimate dynamic ride height. The idea of the bump is to make that travel predictable. If it is doing its job, why would you need to remove shims? Doesn't make sense to me.

Basecircle
03-19-2017, 09:04 PM
If the track is rutted up typically in the heat race, but then graded to a smoother surface and slicker for the feature, you may be able to lower the RF considerably. Question is, would it change the handling too much to be worth it? Would it take you completely out of the ballpark or could you make other adjustments and take full advantage? I'm sure it would be better, but might take a lot of testing to get it right

MasterSbilt_Racer
03-19-2017, 10:44 PM
If the track is rutted up typically in the heat race, but then graded to a smoother surface and slicker for the feature, you may be able to lower the RF considerably. Question is, would it change the handling too much to be worth it? Would it take you completely out of the ballpark or could you make other adjustments and take full advantage? I'm sure it would be better, but might take a lot of testing to get it right

Let's say you take out a 1/4" of shims. If you are really using that bump, you dynamic wedge just took a huge hit. You lost tons of drive on exit.

Kromulous
03-20-2017, 08:47 AM
How do you combat the loss in drive with the 1/4" removed?

Well, more hike on the LR would result, so less dynamic LR would be a result too. Add more LR bite, pre-load? Softer LR spring? Maybe a bar change but i don't think 1/4" would warrant that, just thinking out loud here, but the bar change could help take out some rear steer with the added hike.

This is always the struggle with a stack RF too, when and where, and also how long you want to keep the 2nd spring engaged.

fastford
03-20-2017, 02:38 PM
when most people first start experimenting with the bump or stacked 2 stage, they most likely will experience a throttle push because of the load generated to the left rear when the rt frt cant compress any more, some will trail the right rear, which i dont like, you can free it up some moving the bars but what i fond worked best for me was to keep lowering the rt front to gain rear steer , this was my first road block because the more i lowered it, the better it got, until my old out dated frame started hitting the ground. if you dont have an up to date chassis, its probably best to stay conventional on rt frt...

King1
03-20-2017, 06:52 PM
You have a point mbr. I guess it can be whatever you want it to be as an adjusting tool. Just a typical racer fingering things on a race car that shouldn't be fingered after you get it dialed in.

MasterSbilt_Racer
03-20-2017, 07:38 PM
You have a point mbr. I guess it can be whatever you want it to be as an adjusting tool. Just a typical racer fingering things on a race car that shouldn't be fingered after you get it dialed in.
I agree. You can tune it for what you need. And it may be different on different configurations.

King1
03-20-2017, 08:07 PM
And to the above, yes make sure you have a newer car
If you have an older car by all means go ahead it works, just don't hit the brake pedal anytime soon.