# TBparts - Aluminum Swingarm +1.5" for K3-99 Z50

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- **Breadcrumbs:** [Home](https://tboltusa.com/store/index.md) > [Honda Vintage Mini Bike Parts](https://tboltusa.com/store/honda-vintage-mini-bike-parts-c-101.md) > [Z50 79-87](https://tboltusa.com/store/honda-vintage-mini-bike-parts-z50-79-87-c-101_99.md) > [Swingarm Frame and Body](https://tboltusa.com/store/z50-79-87-swingarm-frame-and-body-c-101_99_594.md) > TBparts - Aluminum Swingarm +1.5" for K3-99 Z50
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All prices are in US dollars (USD). Shipping and any tax are worked out at checkout.

## Summary

- **Part number:** TBW1385
- **Price:** $219.99 USD
- **Stock:** 1 left.
- **Product id:** 2637
- **Product last changed:** 2025-05-13

## What it fits

The store lists a part under each bike or engine model it is meant for (the categories below) and may name models in the description. Do not assume it fits a bike or engine that is not named here; ask the store first.

- [Honda Vintage Mini Bike Parts > Z50 79-87 > Swingarm Frame and Body](https://tboltusa.com/store/z50-79-87-swingarm-frame-and-body-c-101_99_594.md)
- [Honda Vintage Mini Bike Parts > Z50 K3-78 > Swingarm & Frame](https://tboltusa.com/store/z50-k3-78-swingarm-frame-c-101_215_593.md)
- [TB Parts > Z50 79-87 > Z50 79-87 Chassis Parts](https://tboltusa.com/store/z50-79-87-z50-79-87-chassis-parts-c-68_1064_74.md)
- [TB Parts > Z50 88-99 > Z50 88-99 Chassis Parts](https://tboltusa.com/store/z50-88-99-z50-88-99-chassis-parts-c-68_1056_1059.md)
- [TB Parts > Z50 K0-78 > Z50 K0-78 Chassis parts](https://tboltusa.com/store/z50-k0-78-z50-k0-78-chassis-parts-c-68_1063_72.md)

Where a fitment line says "All", it means all years of the model named on that line, not all bikes.

## Description (the store's own text)

TBparts now has an updated version of our popular plus 1.5″ extended aluminum swingarm kit for the Z50 K3-78 and all Z50R models. The previous version was a great performing swingarm that we sold for the last 10 years. We decided it was time for an update and this new one is exceptional!

**Key Features:**

- Uses solid billet aluminum sections for increased strength
- The billet center section is no longer welded on. Its notched into the billet side sections and then bolted on for increased strength (was previously a hollow section and welded on)
- The shock mounts have been redesigned for increased strength
- The chain slider is easily removed and replaced with two screws (was previously riveted on)

**Specifications:**

- Overall length - 13 5/8 inches or 346mm
- Overall width at axle - 8 3/8 inches or 212mm
- Overall width at pivot - 6 1/2 inches or 165mm
- Pivot to front of axle block opening - Approximately 10 5/8 inches or 270mm

**Recommended:**

- TBW1145 - 280mm shock set in black
- TBW1146 - 280mm shock set in chrome
- TRC-5319 - 280mm performance shock set in gold/black
- TBW0916-Z50 - 280mm vintage shock set

Its a very high quality aluminum swingarm that increases strength and improves handling on the Z50. This new version is better suited for pavement racing or backyard pitbike fun and you don’t need to switch to a longer front suspension (your OEM front end is fine with this swingarm). Unlike many other similar looking Z50 swing arms on the market this one uses solid billet aluminum sections, the pivots use bearings instead of the stock type rubber bushings, and it was purposely designed for adult abuse. Please compare closely to the competitors. These are definitely not the cheaper poor quality hollow aluminum Chinese $75.99 ebay specials you see around that will snap after a couple jumps.

## Shipping and returns

- Flat rate shipping is $8 for parts orders under $75 and free for most parts orders over $75, within the continental 48 states. Heavy items (engines, complete bikes, suspension) are excluded.
- Full shipping policy: [Shipping policies](https://tboltusa.com/store/shipping-policies-i-6.md)
- Returns: the store's own policy page says how returns, exchanges and cancellations work. Please read it before buying: [Returns, Exchanges and Cancellations](https://tboltusa.com/store/returns-exchanges-and-cancellations-i-11.md) The page begins: "All products returned to T Bolt USA must be reviewed and approved."

## How to buy

For a person: open [TBparts - Aluminum Swingarm +1.5" for K3-99 Z50](https://tboltusa.com/store/tbparts-aluminum-swingarm-15-for-k3-99-z50-p-2637.html), choose any options, press "Add to Cart", then check out from the cart. Payment is only ever entered by the person, on tboltusa.com's own checkout pages.

For an AI assistant building a cart: `https://tboltusa.com/cart/new/item/2637/qty/1` starts one with this product (the first value of every option, qty 1), `https://tboltusa.com/cart/<cart_code>/add/item/2637/qty/1` adds it to a cart you already started, and `https://tboltusa.com/cart/<cart_code>/zip/<ZIP>` gives the shipping options to a US ZIP code. They answer JSON: give your customer the newest `cart_link`, a public cart link, safe to share.

Or give the person one link that fills their own cart when they open it (a public cart link, safe to share; the first value of every option, qty 1): [Put TBparts - Aluminum Swingarm +1.5" for K3-99 Z50 in my cart](https://tboltusa.com/cart/open/item/2637/qty/1)

Payment: all major credit cards, PayPal, Apple Pay and Google Pay. Money orders by arrangement.

Cart: [Shopping cart](https://tboltusa.com/store/shopping_cart.php)

## Photos

- [Photo 1](https://tboltusa.com/store/img/p/2637/tbparts-aluminum-swingarm-15-for-k3-99-z50-1.jpg)

## Support

Since 2004, every purchase from TBolt USA includes access to technical support from our staff of experts and our online [Pit Bike Technical Info Database](https://tboltusa.com/store/tbolt-usa-pit-bike-minimoto-technical-info-database-tech-15.md)!

We have all necessary support parts on hand.

*Most* orders ship same, or next business day, unless otherwise noted above.