# TBParts - 108 Stroker Crank Upgrade Kit for 69-79 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 K0-K2 HARDTAIL](https://tboltusa.com/store/honda-vintage-mini-bike-parts-z50-k0-k2-hardtail-c-101_1123.md) > [Big Bore and Engine Kits](https://tboltusa.com/store/z50-k0-k2-hardtail-big-bore-and-engine-kits-c-101_1123_1125.md) > TBParts - 108 Stroker Crank Upgrade Kit for 69-79 Z50
- **Web page:** [this page on tboltusa.com](https://tboltusa.com/store/tbparts-108-stroker-crank-upgrade-kit-for-69-79-z50-p-10034.html)
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- **Generated:** 2026-11-03 17:36 EST
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All prices are in US dollars (USD). Shipping and any tax are worked out at checkout.

## Summary

- **Part number:** TBW9090
- **Price:** $229.99 USD
- **Stock:** 2 left. This is a kit: the count is how many complete kits can be built from the parts on hand.
- **Reviews:** [1 reviews, average 5 of 5](https://tboltusa.com/store/reviews/tbparts-108-stroker-crank-upgrade-kit-for-69-79-z50-pr-10034.html)
- **Product id:** 10034
- **Product last changed:** 2025-06-03

## 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 K0-K2 HARDTAIL > Big Bore and Engine Kits](https://tboltusa.com/store/z50-k0-k2-hardtail-big-bore-and-engine-kits-c-101_1123_1125.md)
- [Honda Vintage Mini Bike Parts > Z50 K3-78 > Engine Kits and parts](https://tboltusa.com/store/z50-k3-78-engine-kits-and-parts-c-101_215_581.md)
- [TB Parts > Z50 K0-78 > Z50 K0-78 Big Bore and stroker kits](https://tboltusa.com/store/z50-k0-78-z50-k0-78-big-bore-and-stroker-kits-c-68_1063_1070.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)

This kit is for customers who already have our complete 88cc race head kit on their Z50 and want to upgrade to a 108cc.

**Key Features:**

- High quality stroker crank for increased torque
- Includes gaskets needed for crank swap

**Recommended:**

- High volume oil pump - TBW0225-6V
- High speed 2mm drill bit - TRC-5526
- 2 Size clutch tool - WHS-2274
- TB oil cooler kit w/ intake mount - TBW1370
- Sta-bil fuel stabilizer - W-57-1129

**Application:**

- Z50 - 69-79

**Kit Includes:**

- TBW0622 - Stroker crank
- TBW0365 - Piston
- TBW0225-6V - High Volume oil pump
- TBW0287 - Clutch cover gasket
- TBW0334 - Center case gasket
- TBW0206 - Gasket set

## 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 - 108 Stroker Crank Upgrade Kit for 69-79 Z50](https://tboltusa.com/store/tbparts-108-stroker-crank-upgrade-kit-for-69-79-z50-p-10034.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/10034/qty/1` starts one with this product (the first value of every option, qty 1), `https://tboltusa.com/cart/<cart_code>/add/item/10034/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 - 108 Stroker Crank Upgrade Kit for 69-79 Z50 in my cart](https://tboltusa.com/cart/open/item/10034/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/10034/tbparts-108-stroker-crank-upgrade-kit-for-69-79-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.