Rz350 down shifting issues

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GRA400C
Posts: 38
Joined: Fri Aug 09, 2013 1:15 am

Rz350 down shifting issues

#1 Post by GRA400C » Tue Sep 05, 2017 11:39 pm

Working on a RZ 350 for a friend all I've done is install the oil pump and rebuild it I installed a new O-ring on the coolant pipe going into the side cover issue is I take off from my house go down to a stop sign get up to third gear shift back down to first just fine I take off I run through the gears decently aggressively get it all the way to sixth gear go for a few more miles than come to a stop sign and it won't down shift. Doesn't even go to a false neutral. I turn around and try skipping the clutch to get going and keep trying to down shift. Finally get it to go down into 2nd and head back. Again got it into sixth and come up to a stop sign. Shifted down ok. Take off and get it into 4th and try and down shift to go into my driveway. Nothing. Bike not moving but running sitting in my driveway it won't go down. I kill it and finally get it into neutral. Roll bike up put on center stand and then move the back wheel with my right hand and up shift with the left. No issues. Then I shift it all the way back down into 1st no issues. Here it click through all the gears just fine.

Any ideas???
Fresh oil and measured with ratio cup when I filled. Added 1500cc like always and used 10-40 motorcycle oil

hablair
Posts: 137
Joined: Fri Mar 18, 2016 6:20 am

Re: Rz350 down shifting issues

#2 Post by hablair » Wed Sep 06, 2017 7:25 am

Is the clutch lever adjusted properly, or the cable still intact, mine was hanging on by a thread and did the same thing a new cable sorted it, that's the easiest check

Now it gets a bit more complicated drain oil and save as its new

remove RH side cover and ensure the shift star is engaging with the shift lever properly and the shift drum rotates

Check clutch is engaging, disengaging properly, are the clutch springs worn, are the teeth on the clutch basket ribbed or is a plate or steel faulty

also remove LH cover and check the shift lever bush hasn't worn through

remove the shift lever and check for bad grooves and ball bearing hasn't welded itself to the end of the lever

If all ok here, then i think its engine out and split the cases to see what's gone wrong inside with the shift drum bush or forks

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JanBros
Posts: 197
Joined: Tue Jan 20, 2015 8:18 pm
Location: The Land of Francorchamps

Re: Rz350 down shifting issues

#3 Post by JanBros » Wed Sep 06, 2017 12:19 pm

it's inherrant to sequential gearboxes : if the teeth on the sides of the gears in the box are not aligned (meaning the teeth are opposed), you can not shift gear. all riders downshift before they stop because of this. if you can not shift while standing still you need to move one of the 2 gearbox shafts so the teeth are no longer opposed, you can do 2 things :
- let the clutch slip a bit so the ingoing shaft moves a bit
- move the bike a bit for/rearward, so the outgoing shaft moves.
if it runs, you can race it !

Hooligan
Posts: 1966
Joined: Mon Aug 20, 2012 1:37 am
Location: Calgary, Alberta

Re: Rz350 down shifting issues

#4 Post by Hooligan » Wed Sep 06, 2017 7:29 pm

You need to downshift while the bike is moving forward. Attempting to downshift 5 gears while the bike is standing still is a recipe for this kind of problem. In this case the problem is user error. Sorry.
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

Bare
Posts: 1196
Joined: Sun Jan 29, 2006 2:18 am
Location: vancouver

Re: Rz350 down shifting issues

#5 Post by Bare » Wed Sep 06, 2017 8:02 pm

JanBros wrote:it's inherrant to sequential gearboxes : if the teeth on the sides of the gears in the box are not aligned (meaning the teeth are opposed), you can not shift gear. all riders downshift before they stop because of this. if you can not shift while standing still you need to move one of the 2 gearbox shafts so the teeth are no longer opposed, you can do 2 things :
- let the clutch slip a bit so the ingoing shaft moves a bit
- move the bike a bit for/rearward, so the outgoing shaft moves.
Maybe... I bought New in '72 a VW Superbeetle.
It did exactly that 4th Gear clutch in to a stoplight and there was No way to get it into Any other gear.. period.. sans rolling the car a few feet.. by whatever means.
Did this from zero miles onwards
Dealer and his cretin mechanics said it was inherent. They ALL do that sir.. Lying Jerks.

Lived with it for years. Finally had it rebuilt,
Surprisingly it No longer had that problem... something about a missing /displaced Circlip, If I remember correctly.

Notably My yama 350 Doesn't do that.
Neither does my 600rr. Yet both have sequential boxes.
Short answer ; it's Broken Mate. Either Rebuild the damned thing OR live with it.

GRA400C
Posts: 38
Joined: Fri Aug 09, 2013 1:15 am

Re: Rz350 down shifting issues

#6 Post by GRA400C » Wed Sep 06, 2017 9:44 pm

Sorry I'll be a bit more descriptive. I was not trying to come to a stop and shift down 5 gears. I always down shift and use the engine to help slow me down. But when it came to a stop and trying to shift down the entire time will coming to a stop I was stuck in top gear. If that makes any sense.

Garrett

GRA400C
Posts: 38
Joined: Fri Aug 09, 2013 1:15 am

Re: Rz350 down shifting issues

#7 Post by GRA400C » Wed Sep 06, 2017 9:54 pm

hablair wrote:Is the clutch lever adjusted properly, or the cable still intact, mine was hanging on by a thread and did the same thing a new cable sorted it, that's the easiest check

Now it gets a bit more complicated drain oil and save as its new

remove RH side cover and ensure the shift star is engaging with the shift lever properly and the shift drum rotates

Check clutch is engaging, disengaging properly, are the clutch springs worn, are the teeth on the clutch basket ribbed or is a plate or steel faulty

also remove LH cover and check the shift lever bush hasn't worn through

remove the shift lever and check for bad grooves and ball bearing hasn't welded itself to the end of the lever

If all ok here, then i think its engine out and split the cases to see what's gone wrong inside with the shift drum bush or forks
Yes clutch is adjusted correctly and the marks on the clutch arm and case line up perfectly. I do have another clutch cable I can instal as well though and some new springs.

Garrett

tacky1
Posts: 950
Joined: Wed May 13, 2015 1:11 am
Location: Pacifica,,

Re: Rz350 down shifting issues

#8 Post by tacky1 » Thu Sep 07, 2017 12:46 am

Could it be a bent fork or a badly work fork that is getting stuck on the edge of the gear fork slot.
1985 RZv500
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1984 GPZ750 Turbo
1989 VFR750R RC30

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