Will an RD07 engine fit an RD04

[landyandy]

As some of you on here will know, I've had a bit of engine bother with my RD04 ... I've managed to source a good RD07 engine - anyone know if it's going to be a straight swap?

Cheers.

[YEN_POWELL]

I reckon it will be although you will have to use the carbs/airbox/electrics from the RD04. I don't think the engine has changed at all since 1989, all alterations to performance are carb/exhaust/airbox related.

[landyandy]

Yep - I reckon that too - just a bit concerned about some of the engine mounts mainly. Don't suppose you know if the frame around the engine is likely to have been changed at all?

[YEN_POWELL]

The frames are totally different, however I think all the mounts are the same. Most are removable plates, so be sure to keep the ones from your 04 as they will probably be slightly different. When are you planning to swap?

[landyandy]

Within the next couple of weeks with a bit of luck ... there was an Ebay posting for AT parts and the fella has an engine which has done only 10k miles, so it's probably worth a go.

Looks like on an RD07 the lower frame is demountable (it isn't on the 04), but the mounts certainly look similar.

[landyandy]

Right - a brief update on this ...

Just to let you know that the swap will begin tonight, and hopefully complete tomorrow AM ...

Fingers crossed!

[Maverick]

Good luck mate and take some pics of the progress if possible!

[landyandy]

Well, I'm pleased to report that the engine is pretty much a straight swap - the only oddity is that the connector from the voltage regulator (could be the pulse generator actually - the round thing on the opposite side to the clutch) is a 4 pin plug with only 2 pins in. The RD04 regulator/generator gizmo had a 4 pin to 4 pin connector.

Anyway, got all the bits reassembled, but the sod won't start ... turns over fine, but just won't catch. Ran out of time to investigate, as I only took a half day off work to get it installed and up and running (which was always going to be pushing it).

Might be a fuel problem, but might be something to do with the generator.

To expand, if you remove the small plate that covers the generator, on the 04, there are 2 pick-ups, whereas on the 07 there is only one. I'll dig out a pic at some point.

[landyandy]

Right - hopefully this will be the penultimate posting on this subject for me.

Turns out that the reason the bike wouldn't start is because the pickups for the voltage regulator on the flywheel are different between a 1991 RD04, and a 2001 RD07. There are 2 horizontally opposed pickups on the early model, but several pickups close together on the later versions.

After my failure to get the flywheel bolt off, I got the bike collected by my local garage for removal of the bolt - the mechanic also helped himself to the old flywheel, did the swap, and has now reported that the bike is running fine and can be ridden home. Unfortunately, I can't collect it until tomorrow.

All in all, that's excellent news. Not only have I managed to perform a successful diagnosis, but my mechanic did more than was asked of him.

Will give a final update once I have got the bike home and completed (it currently has that 'been down the road' look, as most of the panels are missing).

[Maverick]

Excellent news mate, hope it brings you many happy miles in the future!