Lyn Garland's RD Crankshaft FAQ

Lyn Garland on his TR

A vote of thanks to Lyn Garland for these notes on RD crankshaft part numbers and alternative TZ bits together with alternative con rod dimensions.

At a later date I just might get time to add runout tolerances etc (GFS)

Since Lyn's work is about what you need in the way of parts for splitting and rebuilding your beloved machine's crankshaft, I have put this link to Alph Bearings Crank shaft Reconditioning handbook in PDF format.

Many thanks to Alpha Bearings for initially publishing this work, and if you are in the UK give them a bell for a quote :- +44 (0) 1384-255151

It goes without saying if you are in the USA contact Lyn Garland :- VINTSPCLTY at AOL dot COM

Parts used in a Yamaha RD crankshaft re-build
Yamaha Part Number	Part Description	Quantity required
93306-20621	Bearing, Main RD inner	2
278-11515-00	Seal Labyrinth, RD centre	1
93103-20076	Seal, Crankshaft, Left	1
93103-40077	Seal, Crankshaft, right	1
93310-216E1	Bearing, Con Rod small end	2
93310-422C8	Bearing, Con Rod Big end	2
OR
93310-42255	TZ Bearing, big end	2
90209-22071	Big End Thrust Washers	4
2T2-11651-00	Connecting Rods	2
8G8-11681-00	Big End Crank Pin	2
93450-17025	Circlip, piston pin	4
93306-30549	Bearing, Main RD outer	2 NB
OR
93390-00012	Bearing, Main TZ outer	1 NB

NB:- If you choose TZ outer crank bearings you can only use1, and must be mounted on the ignition end of the crank.

Reason the RD uses helical cut primary gears which produce a side load on the crank and require a circlip to keep the crank from shifting. The TZ uses straight cut primary gears that do not load the crankshaft and uses a different bearing location system (half moon clips in the inner crank bearing area.) You cannot use TZ inner bearings because the crank inner shafts are larger than the RD to handle the higher loads.

Rod Part Number	RT 180	29L	278	2T2
Yamaha Con Rods that can be used in an RD
Big End Slotted	Yes	Yes	Yes	No
Big End Diameter	28.00mm	29.00mm	28.00mm	28.00mm
Big End Width	16 mm	17 mm	16 mm	16 mm
Small End Diameter	20 mm	21 mm	20 mm	20 mm
Small end width	16 mm	18 mm	18 mm	18 mm
Centre to Centre Length	105.00 mm	103.50 mm	103.50 mm	115.00 mm
Beam Thickness	6.00 mm	7.00 mm	7.00 mm	7.00 mm

For further details E-Mail:- KGB-Racing at Saltmine dot Org dot UK

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Back to:- FAQs

Lyn Garland on his TR

A vote of thanks to Lyn Garland for these notes on RD crankshaft part numbers and alternative TZ bits together with alternative con rod dimensions.

Since Lyn's work is about what you need in the way of parts for splitting and rebuilding your beloved machine's crankshaft, I have put this link to Alph Bearings Crank shaft Reconditioning handbook in PDF format.

It goes without saying if you are in the USA contact Lyn Garland :- VINTSPCLTY at AOL dot COM

Parts used in a Yamaha RD crankshaft re-build

Yamaha Part Number

Part Description

Quantity required

93306-20621

Bearing, Main RD inner

2

278-11515-00

Seal Labyrinth, RD centre

1

93103-20076

Seal, Crankshaft, Left

1

93103-40077

Seal, Crankshaft, right

1

93310-216E1

Bearing, Con Rod small end

2

93310-422C8

Bearing, Con Rod Big end

2

OR

93310-42255

TZ Bearing, big end

2

90209-22071

Big End Thrust Washers

4

2T2-11651-00

Connecting Rods

2

8G8-11681-00

Big End Crank Pin

2

93450-17025

Circlip, piston pin

4

93306-30549

Bearing, Main RD outer

2 *NB*

OR

93390-00012

Bearing, Main TZ outer

1 *NB*

NB:- If you choose TZ outer crank bearings you can only use1, and must be mounted on the ignition end of the crank.

Rod Part Number

RT 180

29L

278

2T2

Big End Slotted

Yes

Yes

Yes

No

Big End Diameter

28.00mm

29.00mm

28.00mm

28.00mm

Big End Width

16 mm

17 mm

16 mm

16 mm

Small End Diameter

20 mm

21 mm

20 mm

20 mm

Small end width

16 mm

18 mm

18 mm

18 mm

2 NB

1 NB