I just bought an 88 R that ran great for a week, I took it to the dunes and it continued to run excellent for about two hours then it began to loose power right where the power band once was. It sounded to me like it was too lean. The plug read was slightly so...possibly. So I jetted richer by two sizes and still the same problem. Plug read looks ok if possibly slightly rich now. Got home and took the carb out, thoroughly cleaned and blew compressed air through all passageways, new plug gapped at 32 thousands, looked at the reeds they seem fine, had a spare coil and put it on. Still the same high end miss. Disconnected the kill and tether switch and still the problem persists. Compression is 150 pounds hot. The ignition is original, it's 80 over with a trinity stage 3 port job. Stock reeds and cage. stock carb. FMF fatty pipe and turbine core silencer. Any ideas? Do any of you know the ohms on the coil, primary, and secondary, the stator, and if applicable the crank trigger.

I have a few performance questions as well. Have any of you run nitrous on your Rs, I have on my DS650 and loved it. I'm interested in the Boondocker system as it does not require a fuel pump, any one have it ? Any info on set up etc would be appreciated. Anyone running an electric shifter or CO2? I'd like your help here too?

 

first off!! biggest problem about an R is the eletrical system. You NEED to re-gap at 0.20-0.22!! That will do alot for you. second.... 150 pounds is kinda low. you should have at least 175. Mine is 20 over with a really think head gasket and it has 190 pounds and is very healthy.

 

AAAaaahhhhh!! Thanks, I'll pull the jug and check the rings, and try the narrower gap. But why would it run great and suddenly change? Any other ideas and input on the performance upgrades I'm looking into are very appreciated!

 

it could have had more compression before, but you might have squeaked it (partially seized) and now you have damaged the piston/rings, resulting in loss of compression. Pull the head and check the condition of the cylinder wall, you'll have to drain the coolant to do so.

 

Yeah, it sounds as if you did some damage to your piston. You can melt a little section (especially on exhust side) and there goes your performance and compression.

 

when it cools down does it run normal again?
if so your over heating. check jetting and water pump.

 

No it runs the same hot or cool...I never run it hard until it fully warms up. I use some kind of water wetter to keep the temps down. Never saw any overflow to indicate it was overheating.

I'm in the process of finishing my DS 650(buddy blew it up while on the nitrous...very exspensive and time consuming to work on), hopefully I can tear into the R on Monday. I'll let you know how it goes.

Still very interested in any feedback on the nitrous, and the shifters??

 

i would start with a leak down test before you do anything.

 

Hey that's a good idea too. I don't think it has a crank seal leak though as it starts and idles great, and the plug read is ok to the rich side. I'll get into it today.

Still looking for info on the nitrous and shifter?

Thanks for your input so far

 

PMS! give her about 5-7 days and she'll be fine[img]i/expressions/face-icon-small-wink.gif[/img]