just some thoughts..1999 speedster

[abouels0827]

I've got a 99 speedster, just got the carbs rebuilt and had it out on sunday...man does the thing fly...I also noticed qhen I got it back that they checked and wrote compression on both cylinders. ..165/170 and 170/175...does this sound right to you guys? I was hoping I would have good compression but this sounds to good. I was thinking I'd have low 100s nut bought the boat with out checkin last September. First time I had it out since carbs and wear rings replaced. Also had oil pump on one motor changed and both exhausts welch plug rewelded....now it gets to 7k and holds steady.

Also if anyone who's had a speedster thinks the motors rumbled pretty good. I popped open the back with the motors runnin they seemed to be vibrating pretty good.

 

[jhjesse]

I've got a 99 speedster, just got the carbs rebuilt and had it out on sunday...man does the thing fly...I also noticed qhen I got it back that they checked and wrote compression on both cylinders. ..165/170 and 170/175...does this sound right to you guys? I was hoping I would have good compression but this sounds to good. I was thinking I'd have low 100s nut bought the boat with out checkin last September. First time I had it out since carbs and wear rings replaced. Also had oil pump on one motor changed and both exhausts welch plug rewelded....now it gets to 7k and holds steady.

Also if anyone who's had a speedster thinks the motors rumbled pretty good. I popped open the back with the motors runnin they seemed to be vibrating pretty good.

Congrats on the good boat outing and successful repairs.
Factory compression is 150psi. Unless you have some engine mods, I would say the compression is a little higher than normal, or a defective gauge. Either way it is good to have a good running boat. Have Fun!!

 

[Dr Honda]

Yep... spec is 150. On a fresh rebuild, I've seen 155 to 145.


But... some thoughts....


1) The squash band is too tight. (this can be bad) Look in the manual, and check it. It's not hard. You basically put a length of solder in though the spark plug hole, and mash it with that piston. Then, measure it. (I don't remember the gap off the top of my head)

2) A warm engine will read high. (not a prob)

3) Extra oil in the cyl's will read high. (not a prob)

4) A properly modified "Shaved" head will read high. Here again... not really a prob. BUT... you should run premium fuel. 91 octane can support about 175 to 180 PSI static compression.




Anyway... if your squashband is in spec... run good fuel, and have fun !!

 

[abouels0827]

Thanks doc...I'm not sure why it was high...but the mechanic I gad it at only specializes in jet skis...he has a lot full and rebuilds them all the time...that is ehat was wrote on my engines. I would think he knows how to compressions tests since he does rebuilds and maintenace on them all the time.but it ran great and I put in 93 octane gas.. is that to high ordoes it matter?
Btw love the islandia you have...in the future I may move up to that boat...its sksmoking

 

[Dr Honda]

Thanks... that's been a big project. But the fam loves having the room of the Islandia. Plus... since I have 2 little girls (and the wife) the potty is nice to have on board.


I don't think you need 93. 91 will be fine. But I would still check the squash band. It's an easy test.