What do you think is the best motor ever fitted to a dirt bike?

[TT5 Matt]

those 110's are now 125's and still sold in Asian countries where they have plenty of tow to keep up to the congested traffic, in the Philippines their called xrm's and the latest model has mag wheels and a front disc brake. the xr200 is still there as is has been for over 14yrs complete with a electric leg and now front disc and is a favouroit for super moto mods. another motor that's been around for a long time is the xr100 which is bored and stroked to 155cc now and called a tm155 which is a street bike with wire wheels and drum brakes and is used a lot in tricycle duty where the biggest sidecar ive seen on one was in the country or province and had a seating capacity of 16 people between the 4 on the bike including the driver and 12 in the sidecar with plenty of room on top for sacks of rice etc but my favouroit motor of all time would be the 500 thumper motor sold in tt's,xt's and sr's which is still in production for the Japanese market and has been changed very little in all its years of production and were the only non counter balanced true 2 valve 500 thumper's from japan, the others are just wizz  bang 4t's

[Frank M]

but my favouroit motor of all time would be the 500 thumper motor sold in tt's,xt's and sr's which is still in production for the Japanese market and has been changed very little in all its years of production and were the only non counter balanced true 2 valve 500 thumper's from japan, the others are just wizz  bang 4t's

spot on

[frostype400]

TM400 very user friendly predictable power and great ignition.

[80-85 husky]

you need help with issue of yours Frosty..you need to spend some time with Big K to get a husky balance on life

[oldyzman]

Funny you should say that frosty, just got one of them TM400 5 minutes ago!
Brett

[frostype400]

I hope you realise I am joking post a pic when you get a chance.

On the topic tt and xt500 have a good motor but I think they are pretty heavy I don't mind my 82 xr500 motor wise.

[80-85 husky]

obviously frosty you've never ridden a 510 aircooled husky 4 banger??

[Richo52]

The old HONDA XR 75 4 banger ultra reliable able to be highly modified to almost double capacity and started many a motocrossers career.......and of course its BIG brother CR500 watercooled 2 banger......WHAT 490 Maico lol

[Iain Cameron]

I would say the Yamaha MX\YZ 400 from 1975 to 1978 , for a big bore it has amazing low end and in the hands of a good rider can also get up and scare the crap out of you . Iain . Frosty I'll raise you the Mighty SC500 against your TM400 .

[frostype400]

Yes good match up Ian.

A lot of the old kids bikes were great engine wise compared to the newer ones now in my opinion I think every one has ridden a xr75.

[bigk]

Husky 390 (1980 especially) or the 360's are my favorites. The 370SWM enduro I had for a while was also a fantastic thing as was the SWM 440MC (pure grunt, no hit, just easy to use). I think any Euro 300-500 2t is a good thing, unlike a peaky hard to ride  Suzuki RM400.
K