Tested on a 7,000 cc Bus Engine Filter: What SCHORL’s CIRT Test Means for Your Bike and Car
The short answer
SCHORL’s patented air filter technology was tested at CIRT Pune, a government-recognised automotive testing institute. The filter tested was made for a 7,000 cc turbo diesel engine – the kind used in buses and trucks. It caught 99.2% of the dust and let air pass easily.
Your bike or car engine needs much less air than a bus engine. So the same technology in your filter works with a big safety margin.
What is CIRT?
CIRT means Central Institute of Road Transport. It is in Bhosari, Pune. It tests parts used in buses, trucks, cars and bikes, and works with the State Road Transport Undertakings.
When CIRT tests a part, it measures the result and writes it in a report. It does not just take the company’s word.
Why test a bus engine filter?
Think of it like a bridge. If a bridge is tested with a heavy truck and it holds, you never worry when a bicycle crosses it.
A 7,000 cc turbo diesel engine is the “heavy truck” of air filters:
| Engine | Air it breathes per minute (approx., at high speed) |
|---|---|
| 350 cc motorcycle | about 1 m³ |
| 1,200 cc car | about 3.6 m³ |
| CIRT test (bus engine filter) | 11.3 m³ |
That is about 10 times the air of a 350 cc motorcycle and about 3 times a small car. Every SCHORL filter for bikes and cars is made with the same patented technology – so it works far below the load the technology was tested at. You can ride without worrying about your filter.
The results, in simple words
1. Breathing: easy ✅
CIRT checked how hard the engine must “pull” to get air through the filter. The limit was 250. SCHORL scored 148 – much easier than allowed.
Example: drinking juice through a wide straw is easy; through a thin straw is hard. A good filter is like a wide straw for your engine.
2. Dust caught: 99.2% ✅
CIRT blew special test dust (ISO 12103-1 test dust) through the filter, again and again, until the filter was fully loaded with dust. Even at the end, it caught 99.2% of the dust.
Example: if 1,000 tiny dust grains come in, 992 are stopped. Only 8 get through.
| CIRT test | Minimum required | SCHORL result |
|---|---|---|
| Air resistance (mm of water) | 250 maximum | 148 |
| Dust caught – at start | 92% | 98.68% |
| Dust caught – while filling with dust | 95% | 98.06% – 99.48% |
| Dust caught – fully loaded | 97% | 99.20% |
Test report: CIRT Pune, Sample No. 2399905623, 19 July 2023. Tap the report below to see it in full.
Patented – what does that mean?
SCHORL’s technology holds Indian Patent No. 369501.
A patent is not easy to get. The Indian Patent Office has examiners with science and engineering degrees. They compare the idea with what already exists around the world. The idea must be:
- New – nobody has made it before
- Smart – not an easy copy of an old idea
- Useful – it must work in real life
Example: if you draw a picture and it looks like someone else’s, you can’t call it “your new idea”. A patent is the government saying, “Yes, this idea is really new.”
What riders say
CIRT tested dust capture and airflow – not mileage. Mileage depends on your vehicle, road and riding style. Here is what users have shared on Google and on our store:
Mileage
- Royal Enfield Himalayan 411: 28–30 → 30–33 kmpl in the city; 33 → 38 kmpl on the highway, after about 20,000 km. “Engine vibration went down, the bike became more smooth.” – Ankit G. (Google)
- Royal Enfield Meteor 350: “Pickup, power, sound and mileage increased.” – Bhupendra S. (store review)
- Royal Enfield GT 650: “Got 30+ mileage on highway.” – Parvez S. (Google)
- Fiat Avventura: “Mileage is definitely improved around 1-2 kmpl and high-speed pull feels lighter now.” – Rahul M. (store review)
- Car (900 km trip): “3+ extra mileage on my car.” – Rakesh K. (Google)
- Bajaj Dominar 400: about 26 → about 30 kmpl (Motolethe riding blog, which worked with SCHORL on its DT400 build)
Ride feel
- Jawa 42 Bobber: “Acceleration has exceptionally improved and the responsiveness of the throttle too.” – Yash R. (Google)
- Chevrolet Cruze: “Smooth and pick up increased. Pleasure to drive.” – Richard Q. (store review)
- Bajaj Dominar 400, 2 years: “Improvement in throttle response and mileage.” – Saurabh G. (Google)
Long-term use
- Using since 2017 on Dominar, Himalayan 450, Scrambler 400X and Apache RTR 200: “Bumps up the fuel efficiency, lets the engine breathe better.” – Dipen N. (DNAVLOGS) (Google)
- Royal Enfield Interceptor 650, over a year: “A worthy buy.” – Bijeesh K. (Google)
- Maruti Swift diesel, autocross racing: “Breeze to clean… came out brand new after every wash.” Qualified for the Indian National Autocross Championship finals 2025-26. – Kaustav R. (Google)
These are user-reported results from Google and store reviews. Your results may differ.
Why easy breathing can help your engine
An engine is like a person running. If your nose is blocked, you get tired fast. If you breathe freely, you run better.
When the engine gets air easily and the air is clean, fuel burns better. Less dust also means less dirt and carbon inside the engine.
Care is simple
- Wash every 8,000–10,000 km with liquid detergent and water – no oil needed.
- Dry in air or sun, or with a hair dryer on the cool setting (no heat).
- Built to last up to 1,00,000 km.
- 1-year warranty from delivery. See warranty details.
Frequently asked questions
Yes. A SCHORL filter sample was tested at CIRT Pune in July 2023. It caught 99.2% of test dust when fully loaded.
CIRT tested a SCHORL filter made for a 7,000 cc turbo diesel engine. Bike and car filters use the same patented technology but need much less air, so they work with a big safety margin.
Yes. Indian Patent No. 369501.
Many riders report better mileage, but it depends on your vehicle and riding. CIRT tested dust capture and airflow, not mileage.
No. Wash with liquid detergent and water, and dry it.
Questions? WhatsApp us on 9011777275.

