I live by Murray and Butner, so I have a lot to say about this.
The route I'm going to share with you is not hard, but it's weird enough that you should try it some day when you have some time.
First of all, find your way to the Terpenning THPRD center. That's the SW corner of Walker & 158th. If you noodle around, you'll find there is a MUP exit at the east end onto Pioneer Road.
- Follow Pioneer east to Meadow, then turn right (south)
- Go up the hill on Meadow, turn left (east) on Downing.
- Pass Meadow Park Middle School (on the right), make oblique left onto Butner Road.
- Follow Butner Road. Continue past Murray (the light). Butner makes a sharp left, then at the stop sign make a right. You're still on Butner. Pass the bridge, then make a the next right (Huntington)
- Swoop down the hill and up, make a left at the second(?) stop sign onto Bowmont.
- Left at the T onto Park Way.
- Follow Park Way past the light (Cedar Hills Boulevard), up the hill (past Cedar Park Middle School on the right), to the stop sign.
- Right at the stop sign (Marlowe), then next left (behind Cedar Hills Shopping Center) onto Wilshire.
The above seems complicated, but it's really not bad after you've done it a few times. The trick now is to get you onto the US-26 bike path. You'll cross SR-217 (overpass), and then make a left onto SW 96th. Turn right at the T. If you look on Google maps it looks like one would be forced back to Wilshire vi SW Knollcrest. Not true! The US-26 bike path starts right where Park Way ends.
- Follow the path up the hill
- When it dumps you out on the street, make an immediate left onto Pointer. Note: gear down early; you have about one block of 8% grade.
- At the stop sign, make a left on Camelot Court.
- Immediately after the bridge over US-26, make a right back onto the bike path. The bike path continues up to the Sylvan interchange.
You didn't say where you wanted to go in downtown. If I was planning to go into central westside area, I'd probably continue through the zoo:
- Cross the pedestrian light over Skyline Boulevard, stay on the sidewalk.
- Continue on Canyon Court down to the zoo exit.
- Proceed with an annoying uphill grind through the zoo (Canyon Road) and then turn right on Kingston Drive.
- Follow Kingston Drive down to the Rose Garden.
- Make a left. You're technically still on Kingston Drive.
- Bear right at the end of Kingston (Tichner Drive). Tichner loops back around and turns into Marconi Avenue.
- Make a left onto SW Park Place, which turns into SW Washington Way. Past the reservoir, continue right on SW Lewis and Clark Circle.
- Turn right on SW Park Place.
Congratulations, you are now in SW Portland!
Another simpler but more nervy route from the Sylvan interchange is to just hop on US-26 eastbound at the zoo exit and jump off immediately at SW Jefferson Avenue.
If you're planning to go points south of town, you could cross over US-26 at the Sylvan interchange and then follow Hewett Boulevard up to Broadway or Dosch or what you prefer.
Back at Sylvan, if you're going to get on Hewett Boulevard, you can use the left turn signal for the US-26 eastbound onramp to cross over to a sidewalk:
(In case the image doesn't show up, here's the link: http://maps.google.com/maps?f=q&hl=e....0036&t=h&z=18
However, beware that about 25% of the northbound traffic on Scholls Ferry Road will disregard
their red light and try to make a hood ornament of you when you go to the sidewalk. Be careful!