| Author | Message | ||
     Williamscottrobertson |
Ok, got my cylinders back from hammer, went with a 1212 kit to keep it as close to stock as possible without dumping money in getting the heads machined and yadda yadda for the 1250. Anyways got it back together. Still running like poop and back firing into the carb. Front cylinder much cooler than the rear, can’t hold an idle at 1k rpm without dying. Swap the coil out, same result. Swap the wires out with some old ones I had, same result. Switched the plugs around, same result. Swapped the CDI box with another I had, slightly better, I can hear the front one pick up occasisonally. But still not right. What’s next? Cam position sensor? Maybe I could trouble shoot the front coil lead? Idk I’m at a loss now. | ||
| Williamscottrobertson |
Figured it out on the Facebook group. Had a pinched intake seal on the front. She’s running great now, just have to break it in. | ||
| Akbuell |
Were it me, I would start a bit further back, so to speak. First, check compression on both cylinders. If good, then remove the rocker box cover and confirm both valves are being opened and closed as they should, including amount of lift. If that is good, then yeah, the cam position sensor. The coil and plug wires should be easy to bench check; a good thing to do in any case. Helps eliminate them as problem areas. Hope this helps, Dave | ||
| Hawgford |
timing slipped or cup screw backed off read ya'll its already a new motor rockers should be checked but i bet its in the cone nobody remembers to loctite the cup bolt kiss principle applied from the sunny south ..lol | ||
| Akbuell |
Most excellent! Glad the problem is solved, especially since my list was nowhere near the problem. And thanks much for posting the solution. Adds to the community knowledge. Ride safe and enjoy! Dave  | ||
| Hawgford |
yep kiss principle applied and ya didn't have to dig in deep as i was hopin not to hear.Seen many intakes seals bypassed as a problem area.These are cheap,come included with most CV carb rebuild kits,no reason not to have some on hand never get more than 10k on them and make yourself the intake bolt allen tool from a long allen wrench.One end right angle 1/8in tall max and turn the other end into a " ball end" by careful grindin,always remember to snug down evenly..These seals are Not Buell specific and are the same big twin and sporty evo motor 1990-2006... | ||
| 89rs1200 |
Like this one, I have used for years! Looks like 90 degree bends, but they are just a bit more than 90 degrees. $10.76 ; https://www.denniskirk.com/yost-performance/intake-manifold-wrench-wrnb.ph28700.prd/H28700.sku  http://yostperformance.com/products/tools.php This is an interesting tool. Kastar & Lang make them. Rather overkill for home use when the Yost tool works just fine. $41.36; https://www.denniskirk.com/lang-tools/intake-manifold-wrench-5530.p283494.prd/283494.sku  | ||
| Williamscottrobertson |
I put the 5/16 12 point head screws on the back side, left the hex up front because I couldn’t get a 16point ratchet wrench over the front bolts. Nice tool, I’ll have to try those. I screwed up, because I was mounting a new hsr 42 at the same time and I left the rears a little loose so I could move the manifold easily until I mounted the carb, then tightened the rears down. Don’t do that, the carb pushes the seals out of the back lol. I tightened it all up THEN mounted the carb no problem. | ||
| Hawgford |
Yep its very tight in several places squeezing in the 42.i just did one myself.make sure its not touching anywhere and you have shim washers in 2 places on banjo bolts[ breather].Make sure none of the MIk adapter holes are blocked..I've seen some scary"pro" use of orange goop.NEVER use it. | ||
| Williamscottrobertson |
I think I’m going back to the CV until I can get it dialed in. At 2 turns on the air screw I can’t get it to idle less than 1150rpm. I can turn the air screw to 1/4 out from seated and get it to idle around 1k rpm so, somethings up. It’s jetted 17.5/160/-97 needle on the middle clip. |
