I am using a Titanium lower shock bolt on my rebelle with a securing nut. That shock clevis does not have a captive nut.
So far so good, but you got me thinking of going back to steel.
Here is what I use:
https://www.ebay.com/itm/133507068513?var=432966129569Made to DIN 6921 specifications
1.25mm or 1.50mm pitch
Made from certified Titanium Grade 5 6AL-4V bar
Rolled threads for greater fatigue strength
Super strong 120ksi yield strength capability
Corrosion resistant w/ reduce galling
Manufactured to ISO 9001 Quality Standards
Same strength as steel - Nearly half the weight!
Quality inspected before shipping
LIFETIME WARRANTY
Made in the USA
Asked Grok about suitability of the above bolt:
Yes, this titanium bolt appears suitable for use as a lower shock clevis bolt on a very heavy motorcycle (e.g., touring models like a Harley-Davidson Electra Glide or Honda Gold Wing, which can exceed 800–900 lbs fully loaded), provided it's sized correctly for the application (matching the OEM bolt's diameter, length, and thread pitch) and installed with proper torque specs and anti-seize to prevent galling. However, steel bolts are often the default choice in such positions for reasons I'll explain below. Let's break this down based on the bolt's specs, material properties, and real-world usage in motorcycle suspensions.
Key Material Comparison: Titanium Grade 5 vs. Steel
The bolt is made from certified Titanium Grade 5 (Ti-6Al-4V), which is a common aerospace-grade alloy. Its advertised 120 ksi (about 827 MPa) yield strength is comparable to high-strength steel bolts (e.g., SAE Grade 8 or ISO 10.9, which have yield strengths around 130 ksi / 896 MPa). Here's a quick table summarizing pros/cons for this specific application, where the bolt acts primarily as a shear pin (in double shear through the clevis yoke connecting the shock to the frame or swingarm) under high loads, vibrations, and potential impacts:
Titanium Grade 5 (This Bolt)Steel (e.g., High-Strength Alloy like Grade 8)StrengthHigh tensile/yield (120 ksi yield; ultimate tensile ~138 ksi / 950 MPa). Shear strength ~79 ksi (550 MPa). Matches or exceeds many steel bolts in critical loads.Slightly higher in some grades (e.g., 130 ksi yield). More ductile, with better elongation (12–18%) before failure.Weight~45–50% lighter than steel equivalents—useful for reducing unsprung weight in suspension, improving handling on heavy bikes.Heavier, but negligible impact on a very heavy motorcycle unless you're chasing every gram (e.g., for racing).Corrosion ResistanceExcellent; resists rust from road salt, moisture, or off-road exposure without coatings. Ideal for long-term use on touring/heavy bikes.Prone to rust unless zinc-plated or stainless (stainless steel is corrosion-resistant but ~15–20% weaker than alloy steel).Fatigue ResistanceGood with rolled threads (as specified), which enhance durability under cyclic loads like bumps/vibrations. Lower modulus of elasticity (~16 msi / 110 GPa) allows more flex/stretch, potentially absorbing shocks better than stiffer steel.Excellent; higher modulus (~29 msi / 200 GPa) makes it stiffer, but it can handle repeated flex without cracking as readily in high-vibration spots.Galling/WearReduced galling per specs (likely due to surface treatment), but titanium can still seize in threads if not lubricated—use anti-seize compound.Less prone to galling; easier to torque without issues. Better for pins/locating roles where wear from movement occurs.Cost & AvailabilityMore expensive (2–5x steel); specialized, with lifetime warranty here.Cheaper and widely available; OEMs often use steel for cost/reliability.Potential DrawbacksSlightly more brittle in extreme overloads (lower elongation ~10–15%); can fatigue if undersized or over-torqued. Not ideal if the bike sees extreme abuse (e.g., heavy off-roading).Heavier; corrodes faster without maintenance.
"Same strength as steel" claim: This holds true when comparing to equivalent-grade steel bolts. Titanium's strength-to-weight ratio is superior, but in absolute terms, steel can offer a slight edge in ductility for shock mounts where the bolt might experience bending or impact loads on a heavy bike.
DIN 6921 specs: This standard ensures the hex flange head provides good clamping and resistance to loosening, which is fine for a clevis application.
Suitability for Lower Shock Clevis on a Heavy Motorcycle
Why titanium works well here:
Shock clevis bolts are under compressive/shear loads from the bike's weight (including rider, passenger, luggage—potentially 1,000+ lbs on heavy tourers) and dynamic forces from riding. Titanium's properties make it a popular upgrade in racing, motocross, and aftermarket parts for brands like Honda CRF, Evil Bikes, and Ibis, where Ti lower shock bolts are sold specifically as replacements for steel OEMs. These reduce weight without sacrificing strength, and the corrosion resistance is a bonus for heavy bikes used in all-weather touring.
In pro racing (e.g., MotoGP), titanium is used in suspension components for weight savings under extreme conditions. User opinions on platforms like X and forums highlight its strength parity with steel while being lighter and rust-proof.
For heavy bikes, the bolt's 1.25mm or 1.50mm pitch (fine threads) provides better load distribution and vibration resistance, aligning with DIN standards.
Why steel might be preferred:
Steel's higher stiffness and ductility make it more forgiving in high-impact or overload scenarios common on heavy motorcycles (e.g., potholes with full load). Titanium can be more "brittle" in feel during torquing, requiring precise tools to avoid snapping. Some mechanics avoid Ti in non-racing apps due to galling risks or higher cost for minimal gains.
If the bike is very heavy and used for utilitarian purposes (not performance-oriented), steel offers a better safety margin without the need for special installation care. OEMs like Harley or BMW often stick with steel for reliability.
No specific warnings against Ti in heavy bike shocks, but general advice: avoid it in areas prone to fatigue cracks (e.g., linkage bolts) unless spec-matched.
Recommendations
Use this titanium bolt if: You're prioritizing weight reduction, corrosion resistance, or aesthetics (e.g., custom build), and the bike isn't subjected to extreme abuse. Confirm the size (e.g., M10 or M12 diameter, common for shocks) matches your motorcycle's OEM spec—check your service manual. Torque to ~70–80% of steel values (consult a torque chart for Ti Grade 5) and use anti-seize.
Stick with steel if: Cost, ease of replacement, or maximum durability under heavy loads is your focus. A high-grade steel bolt (e.g., from ARP or OEM) will perform identically without the premium price.
General tips: Inspect regularly for wear, as any bolt in this position can loosen from vibrations. The lifetime warranty and ISO 9001/USA manufacturing add confidence in quality. If unsure, consult a mechanic familiar with your bike model.
If you provide the motorcycle model or exact bolt size needed, I can refine this further.