When I was a kid, I saw Monster 900 on the cover of some motorcycle enthusiast magazine and it was love at first sight. The big monster has been my dreambike since I realized I wanted a motorcycle, and about a week ago I took the first step towards making that dream a reality
I just got my hands on a project bike, but I may have bitten off more than I can chew. It has a fair share of problems (been scouring the web to try and diagnose the issue, but so far I haven't had much luck pinpointing the issue) -
First, the good -
Bike is almost immaculate cosmetically
Lowish mileage (13k)
Electrical seems fine at first glance, cable routing looks good, no DIY jank as far as I can tell
New tires (nice)
From the mouth of the previous owner (discussing the previous previous owner) the fuel line blew, unsure of whether it was a clog or what - the guy pulled the fuel filter and completely bypassed it which sets off all sorts of red flags in my book.
He also swapped out stock for K&N air filter and sloppily cut the lid of the airbox down.
Bike has some sort of aftermarket carbon exhaust, not sure what the brand is as they all look fairly similar. The bike itself has some unfortunate (maybe minor, maybe major) issues that prevent it from getting on the road
- Low idle, doesn't take throttle well
- Low compression (makes 125-118, spec is 131-160)
- Inconsistent idle (it jumps from 1k - 1.5k - 1k)
- Backfiring out of front end, shop said it seemed to be running fairly lean
- Significantly decreased torque (can't even really roll off before bike stalls)
The previous owner took it to a shop before I got the bike from him, and from the report (which I've attached)
Fuel pressure 48-52psi at all times, lines are routed properly, no kinks
Battery voltage low (I've connected it to a conditioner)
Swapped out whatever was in tank for 91 octane
Backfires into the intake
Low idle, does not take throttle well
Plugs were fouled (they didn't list how), swapped
Tightened belts to spec
LEAKDOWN TEST - GOOD (more on this later)
Low compression (makes 125-118, spec is 131-160)
"Vehicle needs engine work - tear down before quoting"
Several users here had almost identical symptoms, but they never posted resolutions to the problem. I've found suggestions, but as I'm working with a limited repair budget I'd like to make sure everything is done properly/with consideration the first time. I live in the rockies, nearest dealership is on the west coast so it's not feasible to have it diagnosed by professionals unfortunately.
The advice given by the shop before the owner picked it up (days before I purchased the bike from him) was to check the pistons, rings, essentially suggesting a topend rebuild. I'm not opposed to doing so, and I believe I have the skills necessary if I go about it in a logical way, but that rebuild would wipe my budget (~$1500) so I want to be certain that I've troubleshot every conceivable cause of these problems before I start dropping wads on expensive parts.
IN ADDITION that successful leakdown test would suggest it isn't the piston / rings, but I'm not certain and would appreciate the correction if I'm wrong
Based on my limited research and knowledge, those listed symptoms could be.....
ECU incorrectly mapped for the pipes on the bike (not sure if this particular exhaust would require one, pictured below)
TPS sensor issue
O2 sensor issue
Ignition system (coils specifically)
Issues with fueling and exhaust? Possibly clogged injectors resulting in a stream instead of a spray -
Black soot on headers, unsure if it's normal for Ducatis
Additional weirdness, it looks like someone put mighty putty on the oil pressure switch - it wasn't even hand tight, and when I tried to crank the bike in my garage it spewed oil out
- oil is also well past maximum fill level it seems (after losing oil due to switch not tightened)
I've got the Haynes manual, and I've done modest work on a few of my other bikes before (oil changes, KLR doohicky, yamaha cam chain tensioner, etc).
I'm hesitant to take it into a local shop, as nobody in my area is particularly excited about the idea of working on an early 2000s Duck
This is as far as I've gotten. If anyone has advice or suggestions, I'm all ears and would appreciate any direction you can give me -
1.1 MB Views: 17