Originally Posted by dave3235
Yeh it's the base model for the 30hp I'm not sure if it will go to that with just a carb,may be a exhaust would need changing to.I have been pondering on the ideal for a while.,Will it go to a 30hp what do think needs to be changed for the 30hp tune up.If peek revs are stated at 5,500 and the 25hp revs to 6,000 does that mean the 30hp revs 6,500 or is that where the exhaust comes in, Unsure!
Might be worth your while tuning it up, if it's only a couple quid. What year motor is it?
I'm not sure exactly what the differences are, you can check fairly easily with a parts manual, have a look at the timing settings of each engine as well, that usually changes as the power increases. You could check the part no. of the exhausts of the 20/30 to see if they're the same. The carbs might be the same as well, maybe different jets? I'm sure theres guys on here who know more about these motors, they're fairly common