Does anyone know what the difference between a 98 Summit 670 and a Summit X 670 is?

the 98 summit 670 was just the regular motor, late 98 there was a x model released with the high output motor. the ho has higher compression head, bigger carbs 44mm, more timing, that is all i know for sure. both models had 136 inch track I think. the color scheme is different. the 99 would have dpm. not sure if 98 670 had dpm, it may just have HAC-high altitutude compensator.

i said 99 would have dpm, so wouldn't the 98 X. If both are 98 models I would assume color would be same for some reason I was stuck thinking about 99 models. sorry for any confusion. maybe somebody else knows some more specifics?

The 98X had the unpainted tunnel and magnesium chaincase & cover. Doo did this for the diet.

I am pretty sure that the regular summit had 8 tooth drivers and a 2" track while the x came with a 1-3/4 track with the 9tooth drivers to maintain the approach angle. also the H.O. vs the regular 670. Hope this helps.

And the 98 SummitX had the MXZ style gas tank :sly:

'98 SummitX
-unpainted tunnel
-light magnesium chaincase
-9 toot drivers and 1.75x136 track
-Rebuildable HPG shock on rear
-Light weight seat
-MXZ tank
-Pipe with shorter y-pipe
-flat top pistons
-different high compression head
-shorty carb boots
-DPM
-44mm Carbs