Available 
Racetec RR 200/55 ZR17 78W
from £130.76-£284.64.
£130.76-£284.64
Tyre sizes tracked: 200/55 ZR17 78W
METZELER Motorcycle tyre
Racetec SM 125/75 R420 review
METZELER Racetec SM 125/75 R420 looks like a specialist supermoto racing tyre, so the key buying check is whether the exact size, compound and use case match your bike.
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Last verified: 2026-10-07
Quick verdict
Racetec SM 125/75 R420 is a niche METZELER motorcycle tyre aimed at specialist supermoto racing use rather than broad road commuting. The main buying point is exact fitment: confirm 125/75 R420 against your bike, then check whether the live listing offers the compound and specification you need before ordering. Because the retailer page had limited detail available during checking, price, stock, delivery and variant details should be verified on the live checkout page.
Available tyre sizes and prices
Racetec SM 125/75 R420 is listed with 4 tyre size options from £114.27-£183.25. The visible tyre sizes include 125/75 R420, so use the table to compare the option that matches the exact size, colour, format or specification you want. Always confirm the final checkout price, delivery charge and stock status on the retailer page.
Key product details
These are the retailer details worth checking first for Racetec SM 125/75 R420: Brand: METZELER; Type: Motorcycle tyre; Tyre Sizes tracked: 125/75 R420; Price range: £114.27-£183.25. Treat them as a quick fact sheet, then use the retailer page to verify any installation, warranty, delivery or model-number details before buying.
| Brand | METZELER |
|---|---|
| Type | Motorcycle tyre |
| Tyre Sizes tracked | 125/75 R420 |
| Price range | £114.27-£183.25 |
| Owner rating signal | Not enough owner-review data yet |
| Last checked | 2026-10-07 |
What the product page confirms
The confirmed retailer facts are limited but useful: the product is METZELER Racetec SM 125/75 R420, tracked as a motorcycle tyre, with a price range of £114.69-£184.61 and 4 tracked variants. The live retailer page had limited detail available during checking, so key checkout details such as current stock, date code, delivery cost, guarantee wording and the exact compound on offer remain unconfirmed until you check the live page yourself.
What the wider research says
Metzeler positions Racetec SM as a specialist supermoto racing tyre, and the R420 reference here points to the 16.5-inch front range rather than a normal road-bike R17 fitment. The technical databook says the exact size is NHS and tubeless, with K1 described as soft and K2 as medium, so the compound choice depends on setup and temperature rather than a single universal recommendation. Owner-review evidence is sparse for this exact front size, so it is better to shortlist carefully than to lean on rating strength alone.
Buyer trade-offs to compare
For this METZELER Racetec SM 125/75 R420, the trade-off is between specialist racing intent and everyday road usefulness. K1 soft and K2 medium are both real options in the databook, but the better pick depends on your setup, temperature and use pattern rather than a universal hierarchy. At the tracked price range of £114.69-£184.61, it is worth comparing the exact variant you need against more general road-focused motorcycle tyres if you want a broader all-rounder, because the Racetec SM is clearly built around a narrower supermoto racing brief.
Price and value benchmark
At the tracked starting point of £114.69, Racetec SM sits close to the comparable-product median of £109.15, so it reads more like a mainstream-market specialist tyre than a bargain outlier or a premium exception. The tracked spread up to £184.61 shows that variants or seller offers can move the price materially, so compare the live offer with nearby alternatives and check stock before assuming the lowest tracked figure is still available.
Specs versus alternatives
Compared with nearby METZELER options such as Racetec RR 200/55 ZR17 78W, MCE6 Days Extreme 140/80 D18 70M and Tourance NEXT 120/70 R19 60V, this tyre sits in a much narrower use-case. Racetec SM 125/75 R420 is the specialist supermoto racing pick in this group, while Tourance NEXT points toward more general road touring and MCE6 Days Extreme to a different off-road/enduro style. That makes the comparison less about a straight price race and more about whether you need the exact front size and racing purpose this model is built around.
How to read the review evidence
There is not enough owner-review volume for this exact 125/75 R420 front to treat the rating details as a strong verdict. Historical expert commentary praised grip and feedback but also pointed to faster wear than a Michelin comparison, which is useful context but not a current promise for the exact size or compound you may receive. In short, the evidence supports a cautious shortlist approach: verify the exact listing details rather than relying on review strength alone.
Who it suits
This tyre suits supermoto riders who already know they need a 125/75 R420 front and want a race-focused METZELER option with K1 soft or K2 medium compound choices. It is also a sensible shortlist item for shoppers comparing exact fitment, NHS/tubeless status and compound selection before ordering. If your setup is temperature-sensitive or track-specific, the ability to compare variants matters more here than broad marketing language.
Who should avoid it
Avoid this if you need a general-purpose road tyre, a clearly verified load and speed rating from the live listing, or a model you can assume is road-legal without checking. The evidence does not support broad fitment claims, and the page had limited detail available during checking, so road use, stock and exact specification all need verification before purchase. If your bike does not call for 125/75 R420, this is not a near-size alternative to guess at.
Comfort and everyday support
For comfort, the available evidence is thin: no wet-grip, noise or fuel-efficiency labels were supplied, so this METZELER Racetec SM 125/75 R420 should not be chosen on refinement claims. Its specialist racing brief means everyday-road comfort is secondary to exact fitment, compound choice and intended use. If you want a quieter, more relaxed road tyre, compare it against a road-focused alternative and verify the live listing before assuming this front is the right match.
Value verdict
Racetec SM 125/75 R420 offers value only if the exact fitment and specialist use case match your bike, because the price alone does not make it a bargain. The most sensible value check is to confirm the live price, stock, date code and delivery cost, then compare K1 and K2 against alternative supermoto options and any road-biased tyre you were considering. If those checks line up, the price sits in a normal market zone for a specialist motorcycle tyre rather than an obvious premium trap.
Good alternatives to compare
The closest alternatives to compare with Racetec SM 125/75 R420 include Racetec RR 200/55 ZR17 78W, MCE6 Days Extreme 140/80 D18 70M, Tourance NEXT 120/70 R19 60V. Use these cards to check whether a nearby model gives you a better price, a more suitable specification or a clearer match for your space and budget.
Available 
MCE6 Days Extreme 140/80 D18 70M
from £92.05-£135.49.
£92.05-£135.49
Tyre sizes tracked: 140/80 D18 70M
Available 
Tourance NEXT 120/70 R19 60V
from £74.16-£157.49.
£74.16-£157.49
Tyre sizes tracked: 120/70 R19 60V
Retailer details used
Last checked 2026-10-07. The source list below is included to help you check the details behind the comparison. Always confirm the latest price, delivery cost, stock status and product details with the retailer before buying.
More tyres to compare
These related guides and reviews can help you compare nearby options before buying.
Questions about this tyre
Is Racetec SM 125/75 R420 a road tyre or a specialist racing tyre?
The evidence points to a specialist supermoto racing tyre, not a general road-use model. It is best treated as a niche fitment for riders who already know they need 125/75 R420 and want to confirm the exact compound and use case before buying.
What does NHS and tubeless mean here?
NHS means Not for Highway Service, so it is a clear reminder to check intended use rather than assuming public-road suitability. The databook also lists this size as tubeless, but you should still verify the live retailer listing and packaging before ordering.
Should I choose K1 soft or K2 medium?
K1 is the soft compound and K2 is the medium compound, but the right choice depends on setup, riding style and operating temperature. There is not enough product-specific evidence to call one universally better, so compare your conditions and confirm the exact variant on the live page.
What details should I confirm before ordering?
Check the exact 125/75 R420 fitment, the K1 or K2 compound, and the live listing for load rating, speed rating, stock, date code, delivery cost and return terms. Those details matter more here than any broad rating details, because the evidence supports a specialist racing-use decision rather than a general road recommendation.
Is the listed price good value compared with nearby alternatives?
At £114.69 to £184.61, the Racetec SM sits close to the comparable-product median of £109.15, so it is neither an obvious bargain nor a clear premium outlier. Value depends on whether the exact size, compound and supermoto-racing use case match what you need.