Gran Turismo chain tensioner

The Gran Turismo chain tensioner is designed and manufactured to resolve many of the technical issues associated with existing Lambretta products. The tensioner is designed to have the correct fit to the engine casing and be able to accommodate a wide range primary drive combinations.

The design of the tensioner assembly was specifically targeted to resolve technical issues such as:
1. Wide range of primary drive combinations
2. High quality UK manufacture
3. Replaceable wear components
4. Push / pull tensioning
5. Precise fit to engine casing
6. Lowest price universal tensioner available
To fully resolve all of these technical problems properly required the entire assembly to be re-considered from scratch. Every component was re evaluated from a new design and performance criteria.

Part descriptions

1pcs Tensioner mounting plate, CNC machined aluminium
1pcs Tensioner wear shoe, injection moulded plastic
2pcs Custom machined shoe dowel fasteners
2pcs Hex, M6 bolts x long
2pcs Counter sunk, M6 socket heads x long

3. Pre-fitting preparation

The installation of this product will provide you with increased flexibility in primary drive selection. Please view the selection table below for recommended ratios, sizes and fitting positions.

Primary combination Chain length
15/46                                        80
16/46                                        81
17/46                                        81
18/46                                        82
19/46                                        82
15/47                                         81
16/47                                         81
17/47                                         82
18/47                                         82
19/47                                         83

Kit contains the following parts:
1pcs Tensioner mounting plate
1pcs Tensioner wear shoe
2pcs Custom machine shoe dowels
2pcs M6 hex bolts
2pcs M6 counter sunk socket heads

In addition to the kit you will need:
1. Good tools
2. The correct length IWIS chain
3. A chain tension tab washer

Warning! Only use chains with riveted joining links (we recommend IWIS chain). Never use chains with loose or pinned joining links.

4. Installation

Assembly steps:
With the original chain and primary drive removed, re-assemble with the new chain tension

1. Loosely assemble the chain tensioner together so that the shoe is allowed to slide up and down.
2. Check and prepare the 2 M6 tensioner fixing holes in the casing. Use a drop of soft locking compound to prevent socket screws loosening.
3. Offer up and screw down the assembled tensioner assembly.
4. Fit the lay shaft primary drive shims where applicable.
5. Make sure the shoe is correctly positioned for your primary combination
6. Offer up and fit the primary drive and chain assembly.
7. Move the shoe to the correct tensioning position and tighten the M6 hex nuts
8. Torque range 2 .5 – 3.3 ft/lbs (30-40inch/lbs). These settings require a low range ¼” torque wrench.
9. The shoe dowel is designed to bite into the mounting plate and hold the wear shoe firm.
10. Turn the engine over a few times to check fit and clearance
11. Secure M6 hex nuts with the tab washer (not supplied)
12. The M6 counter sunk screws can have increased security by dot punching a small spot between the edge of the fastener and the mounting plate (the same technique used for securing drive side seal plates).

5. Care and maintenance

The tensioner needs no special care or maintenance procedures. Spare parts are available. Ensure you have the correct type and quantity of oil before running your engine. Do not over tighten your chain tensioner.

6. Disclaimer

While every effort has been made to ensure that these instructions are accurate and concise, they are only intended as a guide for general fitting. Your machine may differ slightly from the one described and illustrated.
Granturismo accept no responsibility for any damage or injury caused by the fitting or use of a Granturismo equipment. For additional information please consult the Lambretta workshop manual or your dealer. If you feel that
you are insufficiently equipped to carry out the installation safely and correctly, we recommend you consult your nearest dealer before proceeding.
This conversion kit carries no type approvals. Verifying the legality of the installation for road use is solely the responsibility of the customer/rider

£30 each

Gran Turismo chain tensioner

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