Conti Synchroflex T5 650

Conti Synchroflex T5 650 – dimensionally stable timing belt for positioning and power transmission

Conti Synchroflex T5 650 is an endless, cast polyurethane timing belt with 130 teeth, 5 mm tooth pitch and a pitch length of 650 mm. It is intended for synchronous power transmission, where the driving and driven shafts must follow a fixed tooth ratio without the slippage known from friction-based belt drives. The pitch length is the nominal length measurement in the cord line of the belt and is therefore the measurement that must be compared with the existing belt, the machine's spare parts data and the installed timing belt pulleys. This is the standard version in the specified profile. It must not be confused with a possible GEN III version or a double-sided DL belt with the same pitch length.

Key technical data

• Pitch length: 650 mm
• Number of teeth: 130
• Tooth profile: T5
• Tooth pitch: 5 mm
• Material: cast polyurethane with steel cord
• Brand: Conti Synchroflex

These specifications can be used as a check against the marking on the old belt or against the machine's spare parts list. The pitch length is not necessarily the same as a measurement across the outside of the belt, and the number of teeth is therefore often the safest additional check. If in doubt, both the belt and timing belt pulleys should be examined before ordering a replacement.

What characterizes the T5 profile?

The T-profile is the classic metric timing belt profile with trapezoidal teeth and is described as a standard profile according to DIN 7721. It is used for general synchronous drives, positioning tasks and solutions with significant bending. The simple and proven geometry of the profile makes it widely used, but it still needs to be matched with a T-disc with the same tooth pitch. AT, HTD and other profiles are not automatically interchangeable.

Materials and endless manufacturing

Conti Synchroflex is manufactured by casting, where the polyurethane is precisely shaped to the tool's tooth geometry around the embedded steel cord tension elements. The casting process provides high pitch accuracy over the entire circumference of the belt and a strong connection between PU and cord. The finished timing belt is endless and therefore has no welded joints. The polyurethane provides a wear-resistant tooth and back surface, while the steel cord takes the longitudinal tensile load.

What does the version designation mean?

The product is the regular Conti Synchroflex standard version in the specified profile. Standard and GEN III may have the same pitch length and number of teeth, but they are different product series with different material construction and capacity data. The same applies to a DL belt, which has teeth on both sides. When reordering, the entire profile designation should therefore be checked, not just the length.

How the width variants work

The belt width is not written in the product name because the same pitch length is collected on one product page. The starting pu is 6 mm. Integer widths from 6 to 50 mm can be selected on this product page. The original supplier widths for this length are 6, 8, 10, 12, 16, 20, 25, 32 and 50 mm. Other intermediate sizes are offered as cut-to-size versions of the same type of timing belt sleeve when they are within the selection shown. The number of teeth, pitch length and profile do not change when the width is changed.

Relevant machine tasks

The application examples in the catalogue include office machines, household appliances, positioning drives and control drives. This shows that the profile can be used in both power transmission and motion control. However, the specific belt must only be finally selected when the machine's torque, speed, centre distance and pulley geometry are known. When simply replacing a spare part, the safest method is usually to copy the documented profile, length, design and width.

Before ordering a replacement

When replacing a spare part, the marking on the existing belt should be compared with the product name. Check the profile designation, pitch length, number of teeth, design and width. If the text on the belt has worn away, the number of teeth can be counted and the pitch can be assessed by measuring over several teeth. A single external length measurement is less reliable because the nominal length of the timing belt is indicated in the pitch line.

The discs are part of the overall solution

A belt of the correct length can still function poorly if the pulleys have the wrong profile, are worn or are misaligned. Therefore, check the tooth grooves, flanges, shaft alignment and the number of teeth on the pulleys. For T5, the nominal tooth pitch is 5 mm. The fixed tooth mesh makes the gear ratio reproducible, but only when the belt has sufficient wrap and does not run with constant side pressure.

Practical advice for installation

Proper installation begins with clean, undamaged pulleys with the correct profile. Teeth and grooves should be checked for deposits, bars and wear before the new belt is fitted. The pretension should be based on the drive's calculation and should not be selected based on a random hand feel. After the initial run-in, it is a good idea to check grooveing, noise, temperature and whether the belt runs centrally.

What does belt wear indicate?

A properly running timing belt should move smoothly without continuous contact against one flange. Regularly check the teeth for deformation, the back for ctiming bars and the edges for frayed areas. Abnormal noise or heat can be an early sign of incorrect tension or pulley failure. A systematic check of pulleys and belt is more effective than trying to hide symptoms with lubricant.

Temperature, media and service

The standard material is specified for ambient temperatures from -30 °C to +80 °C. Applications close to the limits, especially below -10 °C or above +50 °C, may require special sizing. The molded PU belt is maintenance-friendly and does not require lubricant. Regular visual inspection is still relevant: look for ctiming bars, frayed edges, shiny tooth flanks, foreign body impressions and abnormal side contact. Sudden changes in noise or grooveing may indicate misalignment, too low tension or worn pulleys.

Answers to typical questions

Conti Synchroflex T5 650: can the belt be used for precise positioning?

The tooth engagement provides a positive, synchronous transmission without the normal slippage of a friction belt. This makes the profile relevant for positioning tasks, but the achievable accuracy also depends on the quality of the pulleys, shaft play, belt pretension, load and the overall machine design.

How many teeth does the Conti Synchroflex T5 650 have?

The belt has 130 teeth. The number of teeth is calculated by dividing the pitch length of 650 mm by the tooth pitch of 5 mm. The result is 130, and this number can be used as an additional check when identifying an existing belt. A different number of teeth means a different pitch length.

Conti Synchroflex T5 650: what is the difference between T5 and a GEN III belt?

This product is the standard version. GEN III is a separate reinforced series with red high-performance PU and denser, two-filament steel cord. The same profile and length therefore do not mean that the products are identical.

Conti Synchroflex T5 650: why can a timing belt make noise?

Noise can be caused by incorrect pretension, skewed pulleys, poor tooth profile compatibility, excessive speed, resonance or worn tooth grooves. Lubrication is not the solution. First check alignment, tension, pulley condition and whether the belt runs without abnormal side contact.

Conti Synchroflex T5 650: how to check if the length is correct?

Count the teeth and check the pitch. 130 teeth times 5 mm gives 650 mm pitch length. Then compare the profile and design with the marking or the machine's spare parts list. A measurement around the outside of the belt alone is not accurate enough.

Conti Synchroflex T5 650: does this PU timing belt need to be lubricated?

No. The timing belt is designed for lubrication-free operation. Oil or grease should not be added to reduce noise as this may mask an alignment, pretension or worn pulley problem. Instead, keep the tooth mesh clean and check the cause of any abnormal noise.

Conti Synchroflex T5 650: what does the steel cord mean for the function of the belt?

The steel cord tension members absorb the longitudinal tensile load and provide high longitudinal stiffness. This helps maintain pitch and position during operation. The cord must not be kinked, exposed or damaged during installation, as local damage can weaken the belt.

Conti Synchroflex T5 650: can T5 be used on a different tooth profile with the same pitch?

No, not without documented compatibility. The 5 mm tooth pitch describes the distance between the teeth, but the shape and clearance of the tooth flanks may differ. The belt must be used with pulleys manufactured for the T5 profile. Visual similarity is not sufficient documentation.

Conclusion

The product brings together the specified T5 profile and length on one side, so that the appropriate width can be selected without creating a separate item for each cut. The main technical data is 650 mm pitch length and 130 teeth. If in doubt about load or pulley compatibility, the drive should be calculated before ordering the belt.