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C and D and E and F - Differences

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One of the most common questions is the "Wot model have I got" - "Does this part fit this model"

You see many parts for sale on ebay that are sold RD250/400. Well sometimes they will but a few parts won"t.

Usually most sellers just don"t realise so you can"t blame them and don"t trust those that say - "It has a seat with a cowl on so it must be a E or F"

Many parts got swapped around during the years.

Starting with the obvious - the numbers!

The frame and engine should match on genuine bikes - No exceptions. But don"t be surprised to find that some owner or other has swapped a blown engine at sometime in a bikes history.


Model Numbers Europe.

1976.. 1A3-000101 C model

1977.. 1A3-100101 D model

1978.. 1A3 110101 E model

1979.. 1A3-330101 F model


1976.. 1A1-000101 C model

1977.. 1A1-100101 D model

1978.. 1A1-110101 E model

1979.. 2V0-000101 Daytona

Besides the frame and engine numbers some of the common differances are shown below.

If your footrests are bolted to the side of the frame as per the photo below then you have a E or F model (1978 - 1980).

Wheels - The RD400 C and D models came with plain alloy coloured wheels with non machined edges (red arrow) to the spokes................

All the later alloy wheels had machined edges to the spokes. I had a 400D brand new with plain alloy coloured wheels other members say that they had D models with machined and painted wheels - so there may have been some cross over. In fact the 1977 Yamaha sales brochures has the 400D with plain wheels and the identicle 250D brochure has the 250 with painted wheels.

The machined edge wheels came painted red or black.

One thing is for sure - wheels with rough cast spoke edges were never painted.


The 250/400 never came with an alloy wheel with a rear drum brake. These types of wheels do appear on some RD"s.

Those wheels either came from a later XS250/400 of are aftermarket made by someone else.

Topic under construction

Ok having just gone through the angst of doing an engine rebuild and cannibalising a 250 c for bits to go on a 250E model can i add to this.

for a start, the primary drive gear is thicker on the 250C, as is the drive ring gear on the clutch basket.  you need the primary drive and the clutch basket to match. moving a bit further back the layshaft gear is different as is the kick start.  The lay shaft gear is thicker and is actually two gears one behind the other.  the kickstart works on the gear closest to the engine and the rev counter drive works off the outer gear.  The rev counter gear is a different size and number of teeth - 250E is smaller.  

Essentially to use the 250C clutch and basket which was my original intention, I have had to cannibalise the rest of the running gear to get it all to align and work.  

Oh yes final point.  I have had to build mine and leave out the rev counter drive.  The final and most frustrating part.  the shaft the rev counter sprocket drives is different, on the 250C it sits prouder from the engine cases and has a shoulder to move the plastic sprocket away from the engine cases to enable the plastic sprocket to mesh with the outer gear of the layshaft.  That was most frustrating because that rev counter shaft can only be changed if you do a full engine strip.  Why was I frustrated - because guess where I was in my engine rebuild when i found all this out - you guessed it with the cases all rebuilt. That is a job that can wait for the next time I need to rebuild that engine

Hope that goes some way to help others!

Wheels: RD250D & RD400D



I can see that there is some confusion about whether the D models had Rough Cast Wheels or whether some had Painted and Polished Spokes.

The USA model RD400E (virtually the same as the European RD400D) had Painted with Polished Spokes Wheels, interchangeable with the European RD400D - this is clearly photographed in one of the USA Sales Brochures for the Silver RD400E.

Your RD250D Sales Brochure with the Black Wheels - are you definately sure that it is not just "shadow" created to make the inside of the Spokes appear to be painted Black, I cannot recall any of the RD250D or RD400D models having such Painted and Polished treatment in their day (back in the 1970"s/1980"s).

I have 2 RD250D Sales Brochure Photos, one for the Silver model but it is clear that the inside of the Wheel Spokes, although they appear to be Black, this is just shadow created by the photography. Ditto for the photo I have of the RD250D in either Chappy or Modena Red (only the RD400D came in that colour)!


Speedometer & Tachometer


Another difference between the models is the Speedometer and Tachometer fitted, there were 3 types (4 if you include the Daytona"F" & "G" models):

1) Early type:


The Speedometer is marked in upper-case for either MPH or KM/H (or KMH). The Tachometer is marked in upper-case for "RPM x 1000. The "Red Line" commences at 7500 RPM (according to the Owner"s Handbook) but maybe 8500 RPM. The Tachometer houses the Idiot Lights for NEUTRAL and HIGH BEAM settings (marked in upper-case).

This Early type of gauges were fitted to all European RD250C and RD400C models from new, it is known to have been fitted to all USA RD400C and some early USA RD400D models.

2) Later type:


The Speedometer is marked in upper-case for either MPH or KMH. The Tachometer is marked in upper-case for "RPM x 1000. The "Red Line" commences at 8500 RPM. The Tachometer houses the Idiot Light for HIGH BEAM setting only (matked in upper-case).

This Later type of gauges were fitted to all European RD250D and RD400D models from new, it is known to have been fitted to later USA RD400D models. It was fitted to all USA RD400E models (very similar in spec. to the European RD400D).

3) E Model type:


The Speedometer is marked in lower-case for either mph or kmh. The Tachometer is marked in lower-case for "rpm x 1000. The "Red Line" still commences at 8500 RPM. The Tachometer houses the Idiot Light for HIGH BEAM setting only (in upper-case).

With the Lights turned on, the Gauges glow Green (instead of White) to illuminate the Engine/Speed Readings. The E Model type of gauges were fitted to all European RD250E, RD400E, RD250F & RD400F models (the RD250F & RD400F models were officially called the "1979 E model" from new to differentiate them from the "1978" E models.

4) Daytona type:


The Daytona "F" & "G" models had re-styled Speedometer and Tachometer fitted, these models were not imported into Europe (because the "LC" models were imported here earlier than elsewhere).


Any idea of the purpose for the bump on the left casing?

I just bought a 400F engine with no left casing and wondering if an earlier version will fit.


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