KPMI +0.003in Oversize Valve Guide - Harley Evolution
About KPMI
Kibblewhite Precision Machining supplies valves, valve springs, guides and complete top-end kits used by professional V-twin engine builders. Its black diamond valves and spring kits are a standard specification on high-lift cam builds.
When rebuilding a Harley Evolution engine, worn valve guide bores can lead to valve instability and oil consumption. These KPMI valve guides are crafted to a +0.003in oversize, providing a precise fit for cylinder heads that require a larger diameter guide. They are engineered to restore proper valve seating and extend the life of your top-end components.
Why riders pick this
- +0.003in oversize for worn guide bores
- Fits both intake and exhaust valve positions
- Precision machined for tight tolerances
- Restores valve stability and oil control
- Compatible with 1984-1999 Harley Evolution engines
These KPMI valve guides are specifically designed for Harley Evolution engines from 1984-1999, offering a robust solution for cylinder heads with worn or damaged valve guide bores. The +0.003in oversize ensures a tight, proper seal after the cylinder head has been machined to accept the larger guide. By maintaining precise valve stem alignment, these guides are critical for consistent engine performance and overall durability, especially in high-stress V-twin environments.
Precision Engineering for Longevity
- +0.003in oversize for worn valve guide bores
- Works for both intake and exhaust valve positions
- Precision-machined for optimal tolerances
- Helps prevent oil leakage and excessive wear
- Direct replacement for 1984-1999 Harley Evolution engines
Essential for a Comprehensive Rebuild
Installation of these oversized valve guides typically requires professional machining of your cylinder heads to achieve the correct bore dimension. This ensures an accurate and secure fit, which is paramount for valve train stability and engine health. These KPMI valve guides are an integral part of any comprehensive Evolution top-end rebuild, ensuring your V-twin runs strong for miles to come.
Specifications
- Brand: KPMI
- Manufacturer Part #: 20-4323C
- Length: 1.05 in
- Width: 3.55 in
- Height: 0.65 in
- Weight: 0.08 lbs
Common questions
What does +0.003in oversize mean for this valve guide?
The +0.003in oversize means this guide is 0.003 inches larger in diameter than a standard guide. It's designed to be used when your cylinder head's valve guide bore has worn beyond stock dimensions and needs to be reamed for a larger guide.
Is this valve guide suitable for both intake and exhaust valves?
Yes, this KPMI valve guide is engineered to fit both the intake and exhaust valve positions on Harley Evolution engines.
Will this guide fit my 2000 or newer Harley-Davidson?
No, this valve guide is specifically designed for 1984-1999 Harley Evolution big twin models. Later models with Twin Cam or Milwaukee-Eight engines use different valve guides.
Ordering from Vtwinbikers
- Brand new, sourced through authorized US distribution — never used, never grey-market.
- Not sure it fits? Use Shop by Bike to filter by your year and model, or email us and we will confirm before you order.
- Harley-Davidson and Indian Motorcycle is all we do, so you are talking to people who ride what you ride.
| BRAND | KPMI |
| TYPE | Engine |
| SKU | 191-57040C |
| WEIGHT | 0.08 lb |
