rt1mx vs dt1mx

[yamayeeha]

Two projects I have been compiling bits for but have a couple of questions. Building them for pre 70.

-Rt1 has genuine gyt barrel + mx piston + gyt(most likely) or webco head and hooker pipe.
-Dt1 is dt1 barrel(needs porting) + mx piston + gyt(most likely) or webco head and NOS torque industries pipe + mx gears.

In regards to the Dt - as I need to get some porting on the dt1 barrel is there any benefits to use modern porting specs as opposed to dt1mx specs. Pipe/piston is obviously old design. What would be the benefits of upgrading these?
I want to make the Dt as strong as I can (within reason) more so that it doesn't end up been a complete second rate experience to the RT. I am not trying to build race winning bikes, just want to have fun on both bikes.

What sprockets for the RT as standard RT2 gearset although have an mx 5th gears to go in if fit.

Any input would be great.

[Iain Cameron]

With the DT 1 you can go to the Yamaha level3 porting this will give quite a peaky motor but as with all increases in power the life of pistons and rings are shorter . as you state you are not a front runner so enjoy it with just a mx1 spec up grade . In my oppinion modern style fat pipes look stupid on pre 70 bikes . The dt1/rt1mx gear clusters and the YZ 250/360 A and B will also fit . You can get a lot more out of improving suspention than eng on these bikes . Iain

Set up as mx1 specs

standard only 38mm carby and pipe

[yamayeeha]

Thanks Iain
Yes, suspension mods sound the go.
Pipe-yes I also like them looking period correct. I was thinking that maybe a slightly more modern spec pipe could be hidden with the under pipe. Where were yours done? as they look great. I would only tackle this if there was significant benefit in bridging the performance gap between the rt. At this point it is a torque industries pipe. I am not wanting or expecting the dt and rt to be the same, just don’t want to hop on the dt and everytime wish I was on the rt. I have never ridden a rt/dt/mx 360 so am I heading in the right direction? Any insight from people who own both and their differences would be appreciated.

Couple of questions for the experts.

1-will the rt with gyt barrel and head be too peaky for the standard rt2 gears?
2-who could port my dt1 enduro barrel to dt1mx spec?
3- anyone have experience with EDC exhaust, are they any good?: I have one on a dt2 and is very peaky. It has been ported back in the day and runs a mx piston. It has standard gearing and really struggles at times. This is probably why I am asking about the rt with gearing and gyt spec.

Any further input would be great.
thanks

[Iain Cameron]

The pipe on my RT was made by GMC . I have 4 bikes with his pipes and when I need any more it will be Geoff I go to . MMT in sydney are whom I have used in the past for porting work ,nice work . Instead of the whole cluster change only the gears you need as the DT/RT/2MX/YZ use the same cases so your choice is almost endless in combo's you can have . Iain