Understanding Titanium (Lightweight build)

[mrooks17]

Those of you that have used titanium bolts/nuts over the years, can you give some feedback. This summer I started down the path of exchanging out rotating parts to titanium. Primary, Secondary, QD2, clutch cover bolts, weight pins, starter cup bolts. I used blue loctite on these without using a primer.
I then ordered a nextech carbon skid last week and was reading his instructions on installing it. He recommends using primer and red loctite. The primer being used to help the metal interact with the loctite. Also read to not use impacts on the titanium.

My question is, will my "non primed" blue loctited rotating parts be ok? Or do I need to take them all back off and prime and blue loctite? I don't want to use red on these rotating bolts as there is a high likely hood I may need to remove them.

 

[ndfb35]

I have gotten away with using blue without issue.

 

[madmax]

If you want any Ti bolts for the engine/bulkhead, let me know. Below before and after for full Ti engine bolt package.

 

[gorillam]

Those of you that have used titanium bolts/nuts over the years, can you give some feedback. This summer I started down the path of exchanging out rotating parts to titanium. Primary, Secondary, QD2, clutch cover bolts, weight pins, starter cup bolts. I used blue loctite on these without using a primer.
I then ordered a nextech carbon skid last week and was reading his instructions on installing it. He recommends using primer and red loctite. The primer being used to help the metal interact with the loctite. Also read to not use impacts on the titanium.

My question is, will my "non primed" blue loctited rotating parts be ok? Or do I need to take them all back off and prime and blue loctite? I don't want to use red on these rotating bolts as there is a high likely hood I may need to remove them.

Loctite / Thread retainer will only do it's job quickly on active materials. Sometimes it sets up quickly sometimes not. Honestly it's probably fine.

 

[joshkoltes]

If you buy the loctite sticks you don't need primer.

 

[PSI 800]

never used a primer in over 35yrs of wrenchin sleds. you should be fine, just make sure you torque everything

 

[kanedog]

You old

 

[boondocker97]

Ti is metal that is high in "toughness" but can deform fairly easily. Similar to stainless and both are more susceptible to galling threads as a result. So one of the primary functions of the thread locker is to provide a lubricant for assembly to protect the threads. Alternative Impact recommends blue on all their fasteners. With the Carbon skid components if a bolt comes loose at all I could see the component movement destroying the carbon surfaces or holes in quick order. Carbon also does not want flexing going on that a loose fastener might permit. So that may be why they want red to be used.

When I've weighed bolts back to back Ti is about half the weight of the steel ones. It takes a lot of steel bolts to make 5lb so Ti will only get you to 2.5lb in that same lot. Once you've got all the rotating parts swapped I recommend focusing on points that are the furthest out from the center of the sled as you are going to feel those differences more in dynamic riding.

Most titanium fasteners are grade 5 equivalents while a lot of bolts on sleds are a grade 8 equivalent. There are some higher strength Ti fasteners available that are heat treated. Rolled vs machined threads and forged vs machined heads play into the fastener strengths as well. So do your research for critical locations.

From what I've read on welded Ti parts if there is purple color in/near the weld area the part has gotten too hot and may be structurally compromised.

Ti is more elastic than steel so it can flex or stretch more under stress and return to its original position and not have plastic (permanent) deformation. So you have to be careful if movement or stretch under stress could be an issue. Chassis bolts probably not a big deal. Head studs or bolts I'd at least want a high strength version to try to limit the stretch under load.

 

[boondocker97]

Just realized this thread is useless without pictures too. Necked down ski mounting bolts, washers, and lock nuts from Race Tech. Top ones for Cat OEM mountain skis. Lower ones for Powder Pros. If you measure the lengths you need you can get more exact when ordering so you don't have a bunch of extra thread sticking out (saving more ounces) or have the shoulder extend all the way through the part as seen on the bolt for the Powder Pros. The necked down sections reduce weight further and shouldn't reduce strength in this case since the ski bolts are in shear only on the thicker sections.

OEM bolt assemblies (both) = 0.56lb
Ti replacement assemblies (both) = 0.22lb

PP Bolt assemblies (both) = 0.35lb
Ti replacement assemblies (both) = 0.16lb

 

[boondocker97]

Race Tech is having Black Friday 20% off Ti bolts for those interested.

 

[kanedog]

I want a certificate of attending boondocker97 titanium school. Thank you for posting the knowledge! I have no ti experience so I’m soaking it all in!

 

[boondocker97]

I want a certificate of attending boondocker97 titanium school. Thank you for posting the knowledge! I have no ti experience so I’m soaking it all in!

Done

 

[KootenayD]

This is awesome! Great thread. I've been playing the fastener game on my lightweight build for a while. Horrendously expensive addiction. I agree the lubricating quality of liquid loctite is a good thing. Having taken many Ti bolts in and out of steel and aluminum, I can say that red loctite is no issue to get apart, no heat required. I find doing a ****ty job with red is about the equivalent of clean, prime and blue. I clean and use red like Franks Red Hot around my sled. It comes apart fine and cleans up easy with acetone. Only thing I think I can add is 'galvanic corrosion'. Ti bolts don't play nice with aluminum, use an anodized Ti bolt if you can. Loctite helps too. Oh, and you can use aluminum fasteners in most body panel/plastic applications. They're cheaper and lighter... Happy gram hunting.

 

[mrooks17]

You aren't kidding it is a "horrendously expensive addiction!" I feel like I now look at steel bolts with my nose up in the air.
I recently put together my nextech carbon skid using loctite primer and red loctite. That combination is instant hardness of the loctite, like 10-15 seconds. If you get a carbon skid, my best advice is to put it together it with primer only (hand tight) and then go through and add the red loctite.
I currently have alternative impact's p85, secondary, and QD2 bolts installed. Only thing I'm nervous about is my p85 drive bolt. If the clutch fails, how much of a mess will it be to remove a broke titanium bolt? Debating on not running it as the stock bolt is Grade 8 steel which is stronger.

 

[KootenayD]

Wife: "Why is this 4" square box that came in the mail insured for $2500??" Me: "Looks like a typo"...

I am running every lightweight mod you can think of and a few you can't. Those Ti primary bolts have a very similar tensile to the steel bolts but Ti as a material responds differently under load. If you're gunnin' for grams, I'd run it, especially in the tried and true P85.

 

[mrooks17]

Haha.
Would you say it’s more or less reliable under load? My P85 has also been lightened and balanced from Patrick

Tell me more about these ones you can’t…

 

[KootenayD]

Haha.
Would you say it’s more or less reliable under load? My P85 has also been lightened and balanced from Patrick

Tell me more about these ones you can’t…

The way the P85 is pinned to the sled is far more reliable than the P22 design and puts less stress on the primary bolt. I think the Steel bolt vs Ti is rather blue on black. If you set that primary bolt correctly and leave it alone, they should both be just fine. Too many guys going OCD on it. Set it, check it, mark it. Shred.

I think the only custom mods worth mentioning are my oil res relocate, Ti bar setup and a full set of carbon steering rods with alum rod ends. After the Ti can went on I felt like the sled was really poorly balanced. Sure enough, on the scale, it was 30lbs different left to right. Balancing the sled has been really helpful with my 'right side commitment issues'. I want to jump to that right side as often as the left without a thought or preference.

 

[xpturbo600]

Titanium primary bolts truly are not worth the risk and money. The reason why is discussed previously but it doesn't seem anyone picked up on it. Mass at a distance from the center of rotation is what creates inertia. If we could truly create a bolt that was perfectly centered on the rotation axis and there was zero dimensional distance about that axis, then the inertia of a bolt that weighs zero pounds is the same as the inertia of a bolt with infinite mass. Let that sink in for a second. If those conditions were true, then the only effect a ti bolt would have over steel is the static weight difference. To be clear, we are talking about the engine dynamics of a primary clutch bolt. If the example holds, the speed with which an engine revs up is identical for a Ti setup and a 1 million pound bolt. The reason I give this example is because mass must be at a distance from the axis of rotation to have inertia effects that change engine dynamic response.

In reality, bolts have some thickness radially, so mass has some effect. But, for a primary bolt, the distance is very minimal about the axis and that matters because the marginal effect on inertia is more sensitive to changes in the distance from center than it is to changes in mass. That is true because radius in the equation for inertia is squared (radius x radius) and mass is just mass. To get higher inertial effects, your mass must be distributed at a distance from the rotational axis. In reality, primary bolts are longer than they are wide, so most primary bolt mass is distributed very close to the axis. Thus, the change in primary bolt weight has minimal inertial effects versus a steel bolt. So, given the risk of not testing clutch bolts to engineer the correct spec relative to steel (as polaris would have), the cost versus benefit/risk does not yield noticeable gains from a performance perspective. However, if you after the static weight difference every gram is weight lost, but it isn't going to yield noticeable differences you can feel on the sled. However, and clutch bolts around the perimeter of the clutch will have a noticeable effect because changing mass at a radius is the first order effect.

All of that is to say, relative to the sleds overall mass, the performance gain from a clutch bolt is negligible, so your better off to use an engineered part for a critical component in the event of failure. If Ti bolts are your thing, and you don't really care about the actual engineering behind it, then it doesn't matter what the performance per dollar outcome is. I hope this helps anyone who is trying to understand what bolts may have the biggest effect on performance.

 

[xpturbo600]

To make sure the effect is clear. Here is the math you need to understand...

Say the change in mass between the bolts is 10 percent. So the heavy bolt is 1.1 pounds and the light bolt is 1.0. Change in mass as a percent is:
(1.1/1.0-1)×100 = 10%

Next, say the change in radius is the same relative percentage for 2 bolts of equal mass...say both are 1 pound bolts. Well use inches for sake of discussion since everyone is likely familiar. Placement of the first bolt is 1 inch from the center of rotation and placement of the second bolt is 1.1 inches from the center of rotation. The effect on inertia as a comparable percentage is:
((1.1x1.1) - (1.0x1.0)) x 100 = 21%

So, a 1 unit change in radius has an effect on inertia that is over double the effect effect of a 1 unit change in mass.

To keep things simple, the relative radius of the primary clutch bolt that is used as the basis for comparison relative to all clutch bolts is 1/2 the radius (diameter/4) of the primary bolt thickness (around the axis of rotation). So, the radius of interest is quite small. That means small bolts near the outer edge of the clutch radially are orders of magnitude more sensitive to changes in mass relative to the primary bolt when it comes to changes in inertia. That is what is implied when I say the effect of changes in radius is squared and why it is the first order effect. That relation is why grams in clutch weights are used as the basis for clutch tuning when for performance changes. Best of luck.

 

[jcjc1]

no way anyone is noticing the weight reduction from running titanium bolts.
spend that money on some sweet ass monster stickers.